Methods of tumor vaccination

ABSTRACT

A method for treating a tumor or generating an immune response against a tumor in a subject in need including a vaccination step comprising administration of a first composition, and a tumor-marking step comprising administration of a second composition, is provided. The first and second composition each comprises an antigenic polypeptide (e.g., a non-tumor antigen) or a nucleic acid encoding an antigenic polypeptide. Also provided are antigenic polypeptides and compositions for use in methods described herein.

RELATED APPLICATIONS

This is a continuation of U.S. patent application Ser. No. 16/857,851,filed Apr. 24, 2020, which claims priority to European PatentApplication No. 19170999.7, filed Apr. 25, 2019, entitled“Pharmaceutical Combination”, International PCT Application No.PCT/NL19/50451, filed Jul. 16, 2019, entitled “PharmaceuticalCombination”, and U.S. Provisional Patent Application Ser. No.62/961,554, filed Jan. 15, 2020, entitled “Methods of TumorVaccination”. The entire disclosure of each of these applications ishereby incorporated herein by reference.

REFERENCE TO SEQUENCE LISTING SUBMITTED ELECTRONICALLY

The content of the electronically submitted sequence listing in ASCIItext file (Name: 719435_DCP9-004BCON_ST25; Size: 7,890 bytes; and Dateof Creation: Jun. 9, 2021) is incorporated herein by reference in itsentirety.

BACKGROUND

Traditionally, and currently still, the focus in therapeutic tumorvaccines is on vaccination with tumor antigens, which are processed byantigen-presenting cells (APC's) such as dendritic cells (DCs) tothereby provide for T cell activation and the mounting of an immuneresponse against the tumor.

The goal of such a vaccination strategy is to enlarge the pool oftumor-specific T-cells from the naïve repertoire, but also to reversetumor-associated dormancy or anergy through the presentation of tumorantigens, in an effort to break central tolerance to those antigens andto overcome blunting of the CD4⁺ and/or CD8⁺ T cell repertoire.

The difficulty in designing therapeutic tumor vaccines, wherepreferentially T-cells against tumor-specific epitopes are stimulated,lies in the propensity of the tumor to evade immune control by alteringitself to reduce expression of the tumor antigens or by creating anenvironment (the tumor micro-environment or TME) that is inhibitory forT cells and other cells of the immune system. In this way, T cellrepertoires that recognize tumor antigens are inactivated, leading toinert or exhausted T cell populations.

Current vaccination approaches are dependent upon the tumor antigensexpressed at a specific moment by the tumor. This means that thesevaccination approaches are circumvented by the immune-evasive propertiesof tumor cells because the natural selection pressure on the tumor isgenerally not strong enough to force the tumor into cell death. Further,it remains difficult to employ tumor-specific antigens that are not alsoself-antigens, the latter being generally tolerized by the immune systemor provide for weak T-cell-mediated immune responses. A current researchfocus in the field of therapeutic tumor vaccines lies in theidentification of inter alia tumor neoantigens. Although theseneoantigens might sufficiently stimulate T-cells following vaccination,they have an intrinsic disadvantage in that they are generallypatient-specific and thus are not suitable as a tumor vaccine that findsbroad application over the patient population. Also, they are not stablyexpressed and may alter over time, making it even more challenging tocompose the correct vaccines formulations. It is clear from the abovethat current tumor vaccination approaches are based on vaccination withtumor antigens and are directed to the antigenic state of a tumor at agiven time point, and thus do not actively manipulate the antigenicstate of the tumor.

Accordingly, there is a need for improved therapeutic tumor vaccinesand/or vaccination strategies, which are not dependent on tumor-antigenexpressed by a tumor, and which incorporate antigens that provide for anoptimal T-cell response upon vaccination. Such improved therapeutictumor vaccines and/or vaccination strategies would be applicable in bothhuman and veterinary use.

SUMMARY

A novel vaccination strategy, also referred to as ‘tumor-antigenindependent vaccination,’ is provided herein. By designing a vaccinationapproach that is independent from tumor antigens, an immune response israised against an antigen that is immunogenic in a subject (e.g., ahuman subject), wherein the antigen is of foreign (e.g., non-human)origin. Such an immunogen provides for a strong immune response, forinstance by activating T-cells from the naïve repertoire or by tappinginto pre-existing immunity by re-activating memory T-cells and/or memoryB-cells that were generated during a prior immune response that was notan immune response against the tumor, and in some cases, was an immuneresponse that occurred prior to establishment of a tumor as the resultof common vaccination against infectious diseases. This principleovercomes the restrictions of tumor antigen-based vaccination methodsdescribed above and is applicable over the entire patient population. Inaddition, tumor-antigen independent vaccinations find value in animalhealthcare, where readily targetable tumor antigens are poorlyavailable, and where there is a high need for cost efficient immunetherapies that are applicable across various species of animals.

In a first aspect, a vaccination strategy comprises administration(e.g., a vaccination step) of an immunogenic composition (e.g., avaccine composition) comprising an antigen that is foreign or exogenousto a subject (e.g., a human subject) as an immunogen. In certainembodiments, the antigen is highly immunogenic, and can be an antigenthat is not, or is only rarely, encountered by the immune system of thesubject (e.g., a human subject) except via common vaccination againstinfectious diseases. In certain exemplary embodiments, a vaccinationstep is performed using a non-human antigen. In certain exemplaryembodiments, a vaccination step is performed by using a non-tumorantigen.

In a second aspect, a vaccination strategy comprises actively marking atumor cell (e.g., a tumor-marking step), or its direct or immediateenvironment (e.g., the tumor site or the tumor micro-environment (TME))with the same antigen that was employed in the first aspect relating tovaccination. In certain exemplary embodiments, the tumor, or its directenvironment (e.g., the tumor site or the tumor micro-environment (TME))is manipulated by presentation of a non-tumor antigen (e.g., anon-human, non-tumor antigen). In certain exemplary embodiments, priorto tumor marking, such an immune response has already been elicited ormounted.

In certain exemplary embodiments, any antigen that is immunogenic in asubject (e.g., a human subject), that is of foreign (e.g., non-human)origin, and that is expected to provide a strong immune response, e.g.,by activating T-cells from the naïve repertoire or by tapping intopre-existing immunity against antigens that are not antigens specific tothe tumor of interest is used: (i) to vaccinate against said antigen soas to mount the desired immune response against said antigen; and (ii)to mark the tumor as a target for such an immune response by allowingpresentation of a corresponding antigen at the tumor site or in thetumor micro-environment. The step of administering the immunogeniccomposition can be performed prior to or subsequent to tumor marking. Incertain exemplary embodiments, one or more vaccination steps areperformed prior to a tumor-marking step.

Accordingly, in certain aspects, a method for generating an immuneresponse against a tumor in a subject comprising: a vaccination stepcomprising administering a first composition to the subject at a sitedistal to a tumor site, wherein the first composition comprises anon-tumor antigen or a nucleic acid encoding the non-tumor antigen; anda tumor-marking step comprising administering a second composition tothe subject at the tumor site, wherein the second composition comprisesthe non-tumor antigen or a nucleic acid encoding the non-tumor antigen,wherein the time between the vaccination step and the tumor-marking stepis between about one day and about 6 months, is provided.

In certain exemplary embodiments, the method further comprises one ormore booster steps each comprising administering a booster compositionto the subject, wherein the booster composition comprises the non-tumorantigen or a nucleic acid encoding the non-tumor antigen. In certainexemplary embodiments, the one or more booster steps occur prior to thetumor-marking step.

In certain exemplary embodiments, the tumor marking-step comprisesadministering the second composition into the tumor or proximal to thetumor.

In certain exemplary embodiments, the vaccination step comprisesadministering the first composition via a route selected from the groupconsisting of intramuscular, subcutaneous, intravenous, intraarterial,intraperitoneal, intrasternal, intradermal, transcutaneous, transdermal,delivery to the interstitial space of a tissue, and delivery to anon-tumor tissue. In certain exemplary embodiments, the vaccination stepcomprises intradermally administering the first composition. In certainexemplary embodiments, the first composition is prepared for intradermalinjection. In certain exemplary embodiments, the first compositioncomprises a diluent or solvent acceptable for intradermal injection. Incertain exemplary embodiments, the vaccination step comprisesintramuscularly administering the first composition. In certainexemplary embodiments, the first composition is prepared forintramuscular injection. In certain exemplary embodiments, the firstcomposition comprises a diluent or solvent acceptable for intramuscularinjection.

In certain exemplary embodiments, the vaccination step comprisesadministering the first composition into an organ system that isdifferent than the organ system in which the tumor resides. In certainexemplary embodiments, the vaccination step comprises administering thefirst composition at a site contralateral to the tumor.

In certain exemplary embodiments, the vaccination step is performedsubsequent to the tumor-marking step. In certain exemplary embodiments,the tumor-marking step is performed subsequent to the vaccination step.In certain exemplary embodiments, the time between the vaccination stepand the tumor-marking step is sufficient for an immune response to bemounted as a result of the vaccination step. In certain exemplaryembodiments, the time between the vaccination step and the tumor-markingstep is about 2 days to about 21 days.

In certain exemplary embodiments, the tumor is a solid tumor. In certainexemplary embodiments, the solid tumor is glioblastoma or ovariancancer.

In certain exemplary embodiments, the first composition comprises adendritic cell comprising the non-tumor antigen or a nucleic acidencoding the non-tumor antigen. In certain exemplary embodiments, thedendritic cell is a CD34-positive, CD1a-positive, and CD83-positivemature dendritic cell. In certain exemplary embodiments, the maturedendritic cell is derived from DCOne.

In certain exemplary embodiments, the second composition is prepared forintratumoral administration. In certain exemplary embodiments, thesecond composition comprises a tumor targeting component. In certainexemplary embodiments, the tumor targeting component is a tumor-specificvirus. In certain exemplary embodiments, the tumor-specific virus is anoncolytic virus. In certain exemplary embodiments, the tumor-specificvirus comprises the non-tumor antigen or a nucleic acid encoding thenon-tumor antigen. In certain exemplary embodiments, the tumor targetingcomponent is a tumor-specific nanoparticle. In certain exemplaryembodiments, the tumor-specific nanoparticle comprises the non-tumorantigen or a nucleic acid encoding the non-tumor antigen.

In certain exemplary embodiments, the second composition comprises adendritic cell comprising the non-tumor antigen or a nucleic acidencoding the non-tumor antigen. In certain exemplary embodiments, thedendritic cell is a CD34-positive, CD1a-positive, and CD83-positivemature dendritic cell. In certain exemplary embodiments, the maturedendritic cell is derived from DCOne.

In certain exemplary embodiments, the first and second compositions eachoptionally comprises one or more pharmaceutically-acceptable carriers,adjuvants, excipients and/or diluents.

In certain exemplary embodiments, the subject is a non-tumorantigen-naïve subject. In certain exemplary embodiments, the subject haspreviously been exposed to the non-tumor antigen. In certain exemplaryembodiments, the subject has previously mounted an immune responseagainst the non-tumor antigen.

In certain exemplary embodiments, the subject is a human. In certainexemplary embodiments, the subject is a domesticated animal and/or ananimal suitable for veterinary healthcare.

In other aspects, a method for generating an immune response against atumor in a subject comprising: a vaccination step comprisingadministering a first composition to the subject at a site distal to atumor site, wherein the first composition comprises a non-tumor recallantigen or a nucleic acid encoding the non-tumor recall antigen; and atumor-marking step comprising administering a second composition to thesubject at the tumor site, wherein the second composition comprises therecall antigen or a nucleic acid encoding the recall antigen, isprovided.

In certain exemplary embodiments, the tumor marking-step comprisesadministering the second composition into the tumor or proximal to thetumor.

In certain exemplary embodiments, the vaccination step comprisesadministering the first composition via a route selected from the groupconsisting of intramuscular, subcutaneous, intravenous, intraarterial,intraperitoneal, intrasternal, intradermal, transcutaneous, transdermal,delivery to the interstitial space of a tissue, and delivery to anon-tumor tissue. In certain exemplary embodiments, the vaccination stepcomprises intradermally administering the first composition. In certainexemplary embodiments, the first composition is prepared for intradermalinjection. In certain exemplary embodiments, the first compositioncomprises a diluent or solvent acceptable for intradermal injection. Incertain exemplary embodiments, the vaccination step comprisesintramuscularly administering the first composition. In certainexemplary embodiments, the first composition is prepared forintramuscular injection. In certain exemplary embodiments, the firstcomposition comprises a diluent or solvent acceptable for intramuscularinjection.

In certain exemplary embodiments, the vaccination step comprisesadministering the first composition into an organ system that isdifferent than the organ system in which the tumor resides. In certainexemplary embodiments, the vaccination step comprises administering thefirst composition at a site contralateral to the tumor.

In certain exemplary embodiments, the vaccination step and thetumor-marking step are temporally separated. In certain exemplaryembodiments, the vaccination step is performed subsequent to thetumor-marking step. In certain exemplary embodiments, the tumor-markingstep is performed subsequent to the vaccination step. In certainexemplary embodiments, the time between the vaccination step and thetumor-marking step is sufficient for an immune response to be mounted asa result of the vaccination step. In certain exemplary embodiments, thetime between the vaccination step and the tumor-marking step is about 2days to about 21 days.

In certain exemplary embodiments, the tumor is a solid tumor. In certainexemplary embodiments, the solid tumor is glioblastoma or ovariancancer.

In certain exemplary embodiments, the first composition comprises adendritic cell comprising the recall antigen or a nucleic acid encodingthe recall antigen. In certain exemplary embodiments, the dendritic cellis a CD34-positive, CD1a-positive, and CD83-positive mature dendriticcell. In certain exemplary embodiments, the mature dendritic cell isderived from DCOne.

In certain exemplary embodiments, the second composition is prepared forintratumoral administration. In certain exemplary embodiments, thesecond composition comprises a tumor targeting component. In certainexemplary embodiments, the tumor targeting component is a tumor-specificvirus. In certain exemplary embodiments, the tumor-specific virus is anoncolytic virus. In certain exemplary embodiments, the tumor-specificvirus comprises the recall antigen or a nucleic acid encoding the recallantigen. In certain exemplary embodiments, the tumor targeting componentis a tumor-specific nanoparticle. In certain exemplary embodiments, thetumor-specific nanoparticle comprises the recall antigen or a nucleicacid encoding the recall antigen.

In certain exemplary embodiments, the second composition comprises adendritic cell comprising the recall antigen or a nucleic acid encodingthe recall antigen. In certain exemplary embodiments, the dendritic cellis a CD34-positive, CD1a-positive, and CD83-positive mature dendriticcell. In certain exemplary embodiments, the mature dendritic cell isderived from DCOne.

In certain exemplary embodiments, the first and second compositions eachoptionally comprises one or more pharmaceutically-acceptable carriers,adjuvants, excipients and/or diluents.

In certain exemplary embodiments, the subject has previously beenexposed to the recall antigen. In certain exemplary embodiments, thesubject has previously mounted an immune response against the recallantigen.

In certain exemplary embodiments, the subject is a human. In certainexemplary embodiments, the subject is a domesticated animal and/or ananimal suitable for veterinary healthcare.

In other aspects, a method for generating an immune response against atumor in a subject comprising: a vaccination step comprisingadministering a first composition to the subject at a site distal to atumor site, wherein the first composition comprises a diphtheria toxinor detoxified variant thereof or a nucleic acid encoding the diphtheriatoxin or detoxified variant thereof; and a tumor-marking step comprisingadministering a second composition to the subject at the tumor site,wherein the second composition comprises a diphtheria toxin ordetoxified variant thereof or a nucleic acid encoding the diphtheriatoxin or detoxified variant thereof, is provided.

In certain exemplary embodiments, the method further comprises one ormore booster steps each comprising administering a booster compositionto the subject, wherein the booster composition comprises the diphtheriatoxin or detoxified variant thereof or a nucleic acid encoding thediphtheria toxin or detoxified variant thereof. In certain exemplaryembodiments, the one or more booster steps occur prior to thetumor-marking step.

In certain exemplary embodiments, the diphtheria toxin or detoxifiedvariant thereof is CRM197.

In certain exemplary embodiments, the tumor marking-step comprisesadministering the second composition into the tumor or proximal to thetumor.

In certain exemplary embodiments, the vaccination step comprisesadministering the first composition via a route selected from the groupconsisting of intramuscular, subcutaneous, intravenous, intraarterial,intraperitoneal, intrasternal, intradermal, transcutaneous, transdermal,delivery to the interstitial space of a tissue, and delivery to anon-tumor tissue. In certain exemplary embodiments, the vaccination stepcomprises intradermally administering the first composition. In certainexemplary embodiments, he first composition is prepared for intradermalinjection. In certain exemplary embodiments, the first compositioncomprises a diluent or solvent acceptable for intradermal injection. Incertain exemplary embodiments, the vaccination step comprisesintramuscularly administering the first composition. In certainexemplary embodiments, the first composition is prepared forintramuscular injection. In certain exemplary embodiments, the firstcomposition comprises a diluent or solvent acceptable for intramuscularinjection.

In certain exemplary embodiments, the vaccination step comprisesadministering the first composition into an organ system that isdifferent to the organ system in which the tumor resides. In certainexemplary embodiments, the vaccination step comprises administering thefirst composition at a site contralateral to the tumor.

In certain exemplary embodiments, the vaccination step and thetumor-marking step are temporally separated. In certain exemplaryembodiments, the vaccination step is performed subsequent to thetumor-marking step. In certain exemplary embodiments, the tumor-markingstep is performed subsequent to the vaccination step. In certainexemplary embodiments, the time between the vaccination step and thetumor-marking step is sufficient for an immune response to be mounted asa result of the vaccination step. In certain exemplary embodiments, thetime between the vaccination step and the tumor-marking step is about 2days to about 21 days.

In certain exemplary embodiments, the tumor is a solid tumor. In certainexemplary embodiments, the solid tumor is glioblastoma or ovariancancer.

In certain exemplary embodiments, the first composition comprises adendritic cell comprising CRM197 or a nucleic acid encoding CRM197. Incertain exemplary embodiments, the dendritic cell is a CD34-positive,CD1a-positive, and CD83-positive mature dendritic cell. In certainexemplary embodiments, the mature dendritic cell is derived from DCOne.

In certain exemplary embodiments, the second composition is prepared forintratumoral administration. In certain exemplary embodiments, thesecond composition comprises a tumor targeting component. In certainexemplary embodiments, the tumor targeting component is a tumor-specificvirus. In certain exemplary embodiments, the tumor-specific virus is anoncolytic virus. In certain exemplary embodiments, the tumor-specificvirus comprises CRM197 or a nucleic acid encoding CRM197. In certainexemplary embodiments, the tumor targeting component is a tumor-specificnanoparticle. In certain exemplary embodiments, the tumor-specificnanoparticle comprises CRM197 or a nucleic acid encoding CRM197.

In certain exemplary embodiments, the second composition comprises adendritic cell comprising CRM197 or a nucleic acid encoding CRM197. Incertain exemplary embodiments, the dendritic cell is a CD34-positive,CD1a-positive, and CD83-positive mature dendritic cell. In certainexemplary embodiments, the mature dendritic cell is derived from DCOne.

In certain exemplary embodiments, the first and second compositions eachoptionally comprises one or more pharmaceutically-acceptable carriers,adjuvants, excipients and/or diluents.

In certain exemplary embodiments, the subject is a human. In certainexemplary embodiments, the subject is a domesticated animal and/or ananimal suitable for veterinary healthcare.

In other aspects, a method for generating an immune response against atumor in a subject, comprising administering to the subject a non-tumorantigen or a nucleic acid encoding the non-tumor antigen at a tumorsite, wherein the subject is previously vaccinated with the non-tumorantigen or a nucleic acid encoding the non-tumor antigen, is provided.

In other aspects, a method for generating an immune response against atumor in a subject, comprising administering to the subject a recallantigen or a nucleic acid encoding the recall antigen at a tumor site,wherein the subject is previously vaccinated with the antigen or anucleic acid encoding the antigen, and wherein the antigen is anon-tumor antigen, is provided.

In other aspects, a method for generating an immune response against atumor in a subject, comprising administering to the subject a diphtheriatoxin or detoxified variant thereof or a nucleic acid encoding thediphtheria toxin or detoxified variant thereof at a tumor site, whereinthe subject is previously vaccinated with the diphtheria toxin ordetoxified variant thereof or the nucleic acid encoding the diphtheriatoxin or detoxified variant thereof, is provided.

In certain exemplary embodiments, the diphtheria toxin or detoxifiedvariant thereof is CRM197.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A-FIG. 1B depict the uptake of subunit KLH protein by DCOne mDCcells (n=3) (FIG. 1A) and the labelling of OV90 ovarian cancer cells(n=2) (FIG. 1B) after 4 hours and 24 hours. 0.08% trypan blue (TB) wasadded to quench extracellular bound subunit KLH-FITC to visualize thepercentage intracellular subunit KLH-FITC.

FIG. 2A-FIG. 2B depict the uptake of β-galactosidase protein by DCOnemDC cells (n=3) (FIG. 2A) and the labelling of OV90 ovarian cancer cells(n=2) (FIG. 2B) after 4 hours and 24 hours. 0.08% trypan blue was addedto quench extracellular bound β-galactosidase-FITC to visualize thepercentage intracellular β-galactosidase-FITC.

FIG. 3 depicts the uptake of CRM197 protein by OV90 ovarian cancer cells(n=2) after 4 hours and 24 hours. 0.08% trypan blue was added to quenchextracellular bound CRM197-Alexa488 to visualize the percentageintracellular CRM197-Alexa488.

FIG. 4A-FIG. 4B depict tumor growth inhibition in a humanized U87-MGglioblastoma model. Tumor size was monitored three times per week usinga digital caliper (FIG. 4A). Tumor size at day 18 in vaccinated miceinjected as indicated is shown in FIG. 4B.

FIG. 5A-FIG. 5B depict tumor growth inhibition in a humanized A375melanoma model. Tumor size was monitored three times per week using adigital caliper (FIG. 5A). Tumor size after day 30 in vaccinated miceinjected as indicated is shown in FIG. 5B.

FIG. 6A-FIG. 6D depict anti-KLH IgG (FIG. 6C-6D) and IgM (FIG. 6A-6B)levels in the serum of mice over time. Anti-KLH IgM and anti-KLH IgMconcentrations (UI/mL) were measured by ELISA using the sera of micetaken at DO, D14 and at sacrifice. N=5 mice per group. Graphs representthe individual data of anti-KLH IgG and IgM per group ((FIG. 6A and FIG.6C) is the glioblastoma group, (FIG. 6B and FIG. 6D) is the melanomagroup). Two-way ANOVA with Dunnet's multiple comparison test was used. *vs vehicle group, *<0.05, **<0.01, ***<0.001, ****<0.0001).

FIG. 7A-FIG. 7D depict the uptake of CRM197 protein by DCOne mDC cells(n=2) (FIG. 7A) and labelling of DCOne progenitor AML cells (n=4) (FIG.7B), OV90 ovarian cancer cells (n=2) (FIG. 7C), and U87 MG glioblastomacancer cells (n=3) (FIG. 7D) after 4 hours and 24 hours. 0.08% trypanblue was added to quench extracellular bound CRM197-Alexa488 tovisualize the percentage intracellular CRM197-Alexa488.

FIG. 8A-FIG. 8B depict tumor growth in a humanized OV90luc ovariancancer mouse model. Tumor volumes (in mm³) were calculated by theellipsoid formula (L×W×H)π/6 (FIG. 8A). Bioluminescence intensity(photons/sec) is depicted (FIG. 8B).

FIG. 9 depicts imaging data showing bioluminescence intensity (totalphoton flux (Optical) per animal) over time.

DETAILED DESCRIPTION

Provided herein are methods for generating an immune response against atumor in a subject. The methods generally comprise a vaccination stepcomprising administering a first composition to a subject at a sitedistal to a tumor site, wherein the first composition comprises anon-tumor antigen or a nucleic acid encoding the non-tumor antigen, anda tumor-marking step comprising administering a second composition tothe subject at the tumor site, wherein the second composition comprisesthe same non-tumor antigen (or nucleic acid encoding the same non-tumorantigen).

The term “immune response,” as used herein, includes T-cell mediatedand/or B-cell mediated immune responses. Exemplary immune functions of Tcells include, e.g., cytokine production and induction of cytotoxicityin other cells. B-cell functions include antibody production. Inaddition, the term includes immune responses that are indirectlyaffected by T-cell activation, e.g., antibody production and activationof cytokine responsive cells, e.g., macrophages. Immune cells involvedin the immune response include lymphocytes, such as B cells and T cells(CD4⁺ and CD8⁺ cells); antigen presenting cells (e.g., professionalantigen presenting cells such as dendritic cells, macrophages, Blymphocytes, Langerhans cells, and non-professional antigen presentingcells such as keratinocytes, endothelial cells, astrocytes, fibroblasts,oligodendrocytes); natural killer cells; myeloid cells, such asmacrophages, eosinophils, mast cells, basophils, and granulocytes. Incertain embodiments, the term refers to a T-cell mediated immuneresponse. The immune response may in some embodiments be a Tcell-dependent immune response. The skilled person understands that thephrase “immune response against a tumor” also includes immune responsesagainst a non-human antigenic polypeptide that is introduced into thetumor micro-environment by intratumoral administration, such asintratumoral administration of (i) dendritic cells, including autologousor allogeneic dendritic cells, loaded with said polypeptide or (ii)viruses comprising a nucleic acid encoding said polypeptide.

The term “T-cell dependent immune response,” as used herein, refers toan immune response wherein either T-cells, B-cells or both T- and B-cellpopulations are activated, and wherein T-cells further assist T and Bcells and other immune cells in executing their function.

The term “tumor,” as used herein, includes reference to cellularmaterial, e.g., a tissue, proliferating at an abnormally high rate. Agrowth comprising neoplastic cells is a neoplasm, also known as a“tumor,” and generally forms a distinct tissue mass in a body of asubject. A tumor may show partial or total lack of structuralorganization and functional coordination with the normal tissue. As usedherein, a tumor is intended to encompass hematopoietic tumors as well assolid tumors. In certain embodiments, the tumor is a solid tumor. Theterm “tumor,” as used herein, includes reference to the tumormicro-environment or tumor site, i.e., the area within the tumor and thearea directly outside the tumorous tissue. In certain embodiments, thetumor micro-environment or tumor site includes an area within theboundaries of the tumor tissue. In certain embodiments, the tumormicro-environment or tumor site includes the tumor interstitialcompartment of a tumor, which is defined herein as all that isinterposed between the plasma membrane of neoplastic cells and thevascular wall of the newly formed neovessels. As used herein, the terms“tumor micro-environment” or “tumor site” refers to a location within asubject in which a tumor resides, including the area immediatelysurrounding the tumor.

A tumor may be benign (e.g., a benign tumor) or malignant (e.g., amalignant tumor or cancer). Malignant tumors can be broadly classifiedinto three major types: those arising from epithelial structures arecalled carcinomas, those that originate from connective tissues such asmuscle, cartilage, fat or bone are called sarcomas, and those affectinghematopoietic structures (structures pertaining to the formation ofblood cells) including components of the immune system, are calledleukemias and lymphomas. Other tumors include, but are not limited to,neurofibromatosis. In certain exemplary embodiments, the tumor is aglioblastoma. In certain exemplary embodiments, the tumor is an ovariancancer (e.g., an epithelial ovarian cancer, which can be furthersubtyped into a serous, a clear cell, an endometrioid, a mucinous, or amixed epithelial ovarian cancer).

Solid tumors are abnormal masses of tissue that can be benign ormalignant. In certain embodiments, solid tumors are named for the typeof cells that form them (such as sarcomas, carcinomas, and lymphomas).Examples of solid tumors, such as sarcomas and carcinomas, include, butare not limited to, liposarcoma, fibrosarcoma, chondrosarcoma,osteosarcoma, myxosarcoma, and other sarcomas, mesothelioma, synovioma,leiomyosarcoma, Ewing's tumor, colon carcinoma, rhabdomyosarcoma,pancreatic cancer, lymphoid malignancy, lung cancers, breast cancer,prostate cancer, ovarian cancer, hepatocellular carcinoma,adenocarcinoma, basal cell carcinoma, sweat gland carcinoma, squamouscell carcinoma, medullary thyroid carcinoma, pheochromocytomas sebaceousgland carcinoma, papillary thyroid carcinoma, papillary adenocarcinomas,papillary carcinoma, medullary carcinoma, bronchogenic carcinoma,hepatoma, renal cell carcinoma, bile duct carcinoma, Wilms' tumor,choriocarcinoma, cervical cancer, seminoma, testicular tumor, bladdercarcinoma, melanoma, CNS tumors (e.g., a glioma, e.g., brainstem gliomaand mixed gliomas, glioblastoma (e.g., glioblastoma multiforme),germinoma, astrocytoma, craniopharyngioma, medulloblastoma, ependymoma,Schwannoma, CNS lymphoma, acoustic neuroma, pinealoma, hemangioblastoma,meningioma, oligodendroglioma, retinoblastoma, neuroblastoma, and brainmetastases), and the like.

Carcinomas that can be amenable to therapy by a method disclosed hereininclude, but are not limited to, squamous cell carcinoma (varioustissues), basal cell carcinoma (a form of skin cancer), esophagealcarcinoma, bladder carcinoma, including transitional cell carcinoma (amalignant neoplasm of the bladder), hepatocellular carcinoma, colorectalcarcinoma, bronchogenic carcinoma, lung carcinoma, including small cellcarcinoma and non-small cell carcinoma of the lung, colon carcinoma,thyroid carcinoma, gastric carcinoma, breast carcinoma, ovariancarcinoma, adrenocortical carcinoma, pancreatic carcinoma, sweat glandcarcinoma, prostate carcinoma, papillary carcinoma, adenocarcinoma,sebaceous gland carcinoma, medullary carcinoma, papillaryadenocarcinoma, ductal carcinoma in situ or bile duct carcinoma,cystadenocarcinoma, renal cell carcinoma, choriocarcinoma, Wilm's tumor,seminoma, embryonal carcinoma, cervical carcinoma, testicular carcinoma,nasopharyngeal carcinoma, osteogenic carcinoma, epithelial carcinoma,uterine carcinoma, and the like.

Sarcomas that can be amenable to therapy by a method disclosed hereininclude, but are not limited to, myxosarcoma, chondrosarcoma, chordoma,osteogenic sarcoma, liposarcoma, fibrosarcoma, angiosarcoma,lymphangiosarcoma, endotheliosarcoma, osteosarcoma, mesothelioma,Ewing's sarcoma, leiomyosarcoma, rhabdomyosarcoma,lymphangioendotheliosarcoma, synovioma, and other soft tissue sarcomas.

The term “subject,” as used herein, refers to the recipient of a methodas described herein, i.e., a recipient that can mount a cellular immuneresponse, and is a mammal. In certain embodiments, the subject is ahuman. In certain embodiments, the subject is a domesticated animal,e.g., a horse, a cow, a pig, a sheep, a dog, a cat, etc. In certainembodiments, the subject is an animal suitable for veterinaryhealthcare, e.g., a zoo animal. The terms “patient” and “subject” may beused interchangeably. In certain embodiments, the subject is a humansuffering from a tumor (e.g., a solid tumor). In certain embodiments,the subject is a domesticated animal suffering from a tumor (e.g., asolid tumor). In certain embodiments, the subject is an animal suitablefor veterinary healthcare suffering from a tumor (e.g., a solid tumor).As used herein, an “animal suitable for veterinary healthcare” is anyanimal that is suitable for treatment by a veterinarian, and includes,without limitation, wild animals, domesticated animals, and zoo animalsthat are capable of mounting a cellular immune response.

The term “polypeptide,” as used herein, refers to a molecule composed ofamino acid monomers linearly linked by amide bonds (peptide bonds). Asused herein, the term is mutually inclusive of the terms “peptide” and“protein” and includes reference to parts of said polypeptides.

The term “nucleic acid,” as used herein, refers to DNA and RNA includingmRNA or cDNA, as well as synthetic congeners thereof. The nucleic acidcan be a recombinant or synthetic nucleic acid.

The term “antigen” or “antigenic,” as used in relation to a polypeptideas described herein, refers generally to a biological molecule whichcontains at least one epitope specifically recognized by a T-cellreceptor, an antibody, or other elements of specific humoral and/orcellular immunity. The whole molecule may be recognized, or one or moreportions of the molecule, for instance following intracellularprocessing of a polypeptide into an MHC peptide antigen complex andsubsequent antigen presentation. The term “antigenic polypeptide” isinterchangeable with “polypeptide antigen.” This terminology includesantigenic parts of said polypeptides, for instance produced afterintracellular processing of a polypeptide and in the context of a MHCpeptide antigen complex. The term “antigen” or “antigenic” includesreference to at least one, or more, antigenic epitopes of a polypeptideas described herein. In certain embodiments, a “non-tumor antigen”refers to herein as an antigen that is not derived from a tumor. Forexample, in certain embodiments, a non-tumor antigen may be a foreignantigen. In certain exemplary embodiments, a non-tumor antigen may be abacterial toxin, e.g., a non-toxic variant of diphtheria toxin.

The term “antigen” or “antigenic” may also be used to refer to apolypeptide that includes modifications, such as deletions, additionsand substitutions to the native sequence, as long as the polypeptidemaintains the ability to be specifically recognized by T-cell receptorsand/or antibodies following vaccination with said polypeptide as animmunogen. These modifications may be deliberate, as throughsite-directed mutagenesis, or through particular synthetic procedures,or through a genetic engineering approach, or may be accidental, such asthrough mutations of hosts, which produce the antigens. Syntheticantigens are also included, for example, polyepitopes, flankingepitopes, and other recombinant or synthetically derived antigens(Bergmann et al. (1993) Eur. J. Immunol. 23:2777 2781; Bergmann et al.(1996) J. Immunol. 157:3242 3249; Suhrbier, A. (1997) Immunol. and CellBiol. 75:402 408; Gardner et al. (1998) 12th World AIDS Conference,Geneva, Switzerland, Jun. 28-Jul. 3, 1998, the disclosures of which areincorporated by reference herein in their entireties). In certainembodiments, the antigenic polypeptide contains at least 1, 2, 3, 4, 5,6, 7, 8, 9 or 10 CD4⁺ T-helper cell epitope(s) and/or at least 1, 2, 3,4, 5, 6, 7, 8, 9 or 10 CD8⁺ cytotoxic T-cell epitope(s).

The term “immunogenic composition,” as used herein, refers to asubstance which induces a specific immune response against an immunogenin a subject who is in need of an immune response against saidimmunogen. The composition may include an adjuvant and optionally one ormore pharmaceutically-acceptable carriers, excipients and/or diluents.The immunogenic composition can be employed in prime-boost vaccination,such as at least 2, 3, 4 or at least 5 immunizations separated in time.The immunogenic composition can be an (allogeneic) dendritic cellcomprising said immunogen.

The term “immunogen,” as used herein, refers to a compound such as apolypeptide capable of eliciting an immune response that is specificallydirected against an antigenic polypeptide as described herein. Animmunogen is also an antigen, i.e., an antigenic polypeptide. Incontrast, an antigen is not necessarily an immunogen. In certainembodiments, the immunogen is used for vaccination (in an immunogeniccomposition such as a vaccine composition), and the antigenicpolypeptide prepared for intratumoral delivery is instead used formarking a tumor as a target for an immune response to be elicited, or asa target for an immune response that is already elicited, in a subject.The term “immunogen” is also used to refer to a nucleic acid whichencodes the non-human antigenic polypeptide as described herein. Inaddition, embodiments that describe the antigenic polypeptide, alsoapply to an immunogen as described herein.

The term “non-human,” as used herein in the context of an antigenicpolypeptide, includes polypeptides that are not of human origin,including a bacterial polypeptide, a polypeptide of an organism of theArchaea domain, a fungal polypeptide and a viral polypeptide. Alsoincluded are plant polypeptides and non-human mammalian polypeptidessuch as polypeptides of non-human primates, rodents (e.g., mice andrats), rabbits, pigs, sheep, goats, cows, pigs, horses and donkeys, andbirds (e.g., chickens, turkeys, ducks, geese and the like). Alsoincluded are polypeptides of snails or other mollusks, includingMegathura crenulata. The term “non-human” also encompasses syntheticpolypeptides, i.e., polypeptides that have an artificial sequencedesigned by man and that do not occur in nature or are not yetidentified in nature. In addition, the term comprises human polypeptidescomprising an amino acid alteration from the native sequence, thealteration providing for immunogenicity in a human subject.

The term “intratumoral,” as used herein, refers to delivery or transportof the antigenic polypeptide, or the nucleic acid encoding saidpolypeptide, into a tumor. One example of intratumoral delivery, ortransport, of an antigenic polypeptide as described herein is byintratumoral administration, a route of administration generally knownin the art. As an alternative route for intratumoral administration, theantigen may be delivered to the tumor via a tumor-specific carrier, suchas an oncolytic virus or a gene therapy vector, which have been broadlydeveloped to deliver gene sequences to tumors. The use of such vehiclesallows for multiple routes of administration, in addition tointratumoral administration, such by as intravenous or intraperitonealadministration, subsequently resulting in the delivery of the nucleicacid encoding said polypeptide, into the tumor (Lundstrom, Diseases,6(2):42 (2018); Alemany, Biomedicines, 2, p. 36-49 (2014);Twumasi-Boateng et al., Nature Reviews Cancer 18, p. 419-432 (2018), thedisclosures of which are incorporated by reference herein in theirentireties).

The phrase “prepared for intratumoral delivery,” as used herein, refersto an antigenic polypeptide as described herein, or a nucleic acidencoding said polypeptide as described herein, that is adapted forintratumoral delivery and/or is in a formulation that allows forintratumoral delivery. The preparation used for intratumoral deliverymay be composed such that it has a beneficial effect on the interactionbetween the immune system and the tumor. For instance, dendritic cells,such as autologous or allogeneic dendritic cells, can be loaded withsaid polypeptide and upon intratumoral administration may provide foradditional immune stimulation via direct interaction with T cellsentering the tumor and/or indirectly by recruiting bystanderantigen-presenting cells (Laurell et al., Journal for Immunotherapy ofCancer, 5:52 (2017); Wallgren et al., Scandinavian Journal ofImmunology, 62, p. 234-242 (2005), the disclosures of which areincorporated by reference herein in their entireties). Another exampleof such preparation is that the polypeptide or nucleic acid as describedherein can be comprised in a tumor-delivery vehicle such as atumor-targeted vehicle including a tumor-specific virus such as anoncolytic virus (or any other virus that selectively replicates in tumorcells) that infects a tumor cell and which allows for (i) expression ofsaid nucleic acid in a tumor cell, and (ii) (subsequently) intracellularprocessing and antigen presentation (MHC) of said (expressed)polypeptide by said tumor cell. The skilled person is well aware ofother methods and means for preparing a polypeptide, or a nucleic acidencoding said polypeptide, for intratumoral delivery. For instance, theskilled person can apply other tumor-targeted delivery vehicles such asa tumor-specific nanoparticle or he can apply intratumoraladministration through intratumoral injection in order to deliver saidpolypeptide or nucleic acid into a tumor. In certain embodiments, thepolypeptide or nucleic acid prepared for intratumoral delivery asdescribed herein, is comprised in a tumor-targeted vehicle.

As used herein, the term “extratumoral” refers to a location, e.g., inthe body of a subject, that is away (e.g., distal) from a tumor andimmediately surrounding tissue (e.g., that may make up the tumormicro-environment).

The compositions for use as described herein, elicit an immune responsespecifically directed against a tumor in a subject. The skilled personunderstands that “specifically directed” refers to an immune responsethat is specific for a tumor. The specificity is introduced by a step ofmarking a tumor with a non-human antigenic polypeptide as a target foran immune response, and by eliciting an immune response against anantigenic part of said non-human antigenic polypeptide (i.e., thetarget). Thus, In certain embodiments, the compositions for use asdescribed herein, is for use in eliciting an immune response against atumor marked as a target for said immune response. In certainembodiments, the compositions for use as described herein, is for use ineliciting an immune response against a tumor that is marked as a targetfor said immune response; wherein said target is a non-human antigenicpolypeptide as described herein.

In certain embodiments, the non-human antigenic polypeptide, or anucleic acid encoding said polypeptide, prepared for intratumoraldelivery as described herein, serves the purpose of marking the tumor asa target for an immune response (polypeptide/nucleic acid for marking atumor). Thus, In certain embodiments, said polypeptide or said nucleicacid prepared for intratumoral delivery marks the tumor as a target foran immune response following intratumoral delivery.

As used herein, the term “vaccination step” refers to a step in a method(vaccination strategy) as described herein, wherein a compositioncomprising an antigenic polypeptide (e.g., a non-tumor antigen) or anucleic acid encoding an antigenic polypeptide is administered to asubject at a site distal to a tumor site. In certain embodiments, in avaccination step of a method as described herein, the composition isadministered at a site that is not the site in which the tumor resides(e.g., not the tumor site). In certain embodiments, in a vaccinationstep of a method as described herein, the composition is administered atan extratumoral site.

As used herein, the term “booster step” refers to a step in a method(vaccination strategy) as described herein, wherein a boostercomposition comprising an antigenic polypeptide (e.g., a non-tumorantigen) or a nucleic acid encoding the antigenic polypeptide isadministered to a subject at a site distal to a tumor site. In certainembodiments, a booster step is performed after a vaccination step,wherein the vaccination step results in an immune response against theantigen, and the booster step enhances the immune response against theantigen. In certain embodiments, a booster step results in an enhancedimmune response in a subject having pre-existing immunity against, e.g.,an antigenic polypeptide (e.g., a non-tumor antigen). In certainembodiments, the vaccination step in a method as described herein is abooster stem, e.g., when the subject has pre-existing immunity against,e.g., a non-tumor recall antigen.

The term “marking,” “mark” or “marked,” as used herein, refers to activemanipulation of the antigenic state of a tumor by intratumoral deliveryof an antigenic polypeptide, or a nucleic acid encoding saidpolypeptide, as described herein. This provides for direct labelling ofa tumor cell through intracellular delivery and subsequent processingand presentation of said polypeptide by said tumor cell, or provides forindirect labelling of a tumor via: (i) intracellular delivery andsubsequent processing and presentation of said polypeptide by anon-tumor cell in said tumor; or (ii) extracellular delivery of saidantigenic polypeptide to said tumor (i.e., extracellular to the cellspresent in said tumor before marking), for instance by using a dendriticcell that comprises a nucleic acid encoding said polypeptide or that isloaded with said antigenic polypeptide. As used herein, the term“tumor-marking step” refers to a step in a method (e.g., a vaccinationstrategy) as described herein, wherein a composition comprising anantigenic polypeptide (e.g., a non-tumor antigen) or a nucleic acidencoding an antigenic polypeptide is administered to a subject at atumor site. In certain exemplary embodiments, the tumor-marking stepcomprises the use of compositions, methods or technologies whichfacilitate the delivery of antigens into the cytosol of tumor cells.

The immunogenic composition as described herein, which also comprisessaid non-human antigenic polypeptide or a nucleic acid encoding saidpolypeptide, but as an immunogen (polypeptide/nucleic acid for elicitingan immune response), serves the purpose of eliciting an immune responseagainst a tumor that is marked, or to be marked, with said non-humanantigenic polypeptide. Thus, in certain embodiments, said immunogen isused to elicit an immune response against a tumor that is marked, or isto be marked, with said non-human antigenic polypeptide, or a nucleicacid encoding said antigenic polypeptide, prepared for intratumoraldelivery. In principle, any antigenic polypeptide can be introduced intoa tumor to generate a new antigenic target. In certain embodiments, anyantigenic polypeptide can be introduced into a tumor to generate newantigenic target that is a B-cell epitope and/or T-cell epitoperecognizable by an antibody and/or T-cell receptor, respectively, whenan immune response against said target is elicited followingadministration of an immunological composition as described herein to asubject.

The skilled person directly understands that: (i) the non-humanantigenic polypeptide, or a nucleic acid encoding said polypeptide,prepared for intratumoral delivery as described herein(polypeptide/nucleic acid for marking a tumor); and (ii) the non-humanantigenic polypeptide, or a nucleic acid encoding said polypeptide,comprised as an immunogen in an immunogenic composition as describedherein (polypeptide/nucleic acid for eliciting an immune response), arematched in that the immunogen, when administered, elicits an immuneresponse that is directed against one or more (target) epitopesestablished by the polypeptide or nucleic acid for marking the tumor.

Thus, for instance, the polypeptides under (i) and (ii) areimmunologically matched in that a T-cell epitope and/or a B-cell epitopeof the marking polypeptide in a tumor are recognized by, or are reactivewith, a T-cell and/or B-cell response elicited by the polypeptideemployed as an immunogen. It is thus understood that the polypeptidesunder (i) and (ii) are based on the same non-human antigenic polypeptideand optionally share an identical antigenic part thereof, optionally atleast one B-cell and/or T-cell epitope thereof (i.e., areimmunologically matched). In this manner, the elicited immune responseis specifically directed to the tumor marked as a target for said immuneresponse. Thus, the formulations of the said polypeptide used foreliciting an immune response on the one hand and tumor marking on theother hand need not be the same. In fact, the skilled person appreciatesthat it might be beneficial to use different formulations of the saidpolypeptide for vaccination and tumor marking.

The term “T-cell mediated immune response,” as used herein, refers to animmune response that is T-cell driven, and where elicitation of anotheror further immune response is dependent on activation of T-cells. Incertain embodiments, the immune response is a T-cell mediated immuneresponse/T-cell dependent immune response. The skilled person is wellaware of methods and means for mounting a T-cell mediated immuneresponse/T-cell dependent immune response, for instance throughselection of an appropriate antigen of which many have been described inliterature including but not limited to bacterial-, fungal-, mollusk-,snail-, insect- or plant-derived antigens to which measurable T cellresponses have been documented, or by selecting an appropriate adjuvantor carrier such as a chemical adjuvant, biological adjuvant, protein,viral vaccine, dendritic cell vaccine or any other composition that canbe administered as a vaccine composition (Bender et al., J. Exp. Med,182:1663-1671 (1995); Bennett et al., Nature, 393:478-480 (1998);Kalinski and Moser, Nature, 5:251-260 (2005); Pashine et al., NatureMedicine Supplement, 11:S63-S68 (2005), the disclosures of which areincorporated by reference herein in their entireties).

The term “tumor-specific virus,” as used herein, includes reference toany virus that has the capacity to selectively replicate in tumor cells.

The term “oncolytic virus,” as used herein, refers to a virus thatpreferentially kills tumor cells as compared to normal cells. Inaddition, the term refers to viruses that can be engineered to carry anucleic acid construct encoding a polypeptide, which is to be expressedin a tumor cell after infection of said tumor cell.

The term “nanoparticle,” as used herein, refers to compositions that cancarry a compound of interest, such as an antigenic polypeptide asdescribed herein, and which can be functionalized on their surface withtumor-targeting or tumor-specific moieties. Examples of nanoparticlesthat can be engineered to actively target tumor cells are micelles andliposomes.

The term “dendritic cell,” as used herein, refers to a professionalantigen presenting cell (APC) that can take up an antigen such as anantigenic polypeptide into its cell, and presents the antigen, or animmunogenic part thereof together with an MHC class I complex or MHCclass II complex. The term includes both immature dendritic cells(“imDC”) and mature dendritic cells (“mDC”), depending on maturity. Incertain embodiments, the dendritic cell is a mature dendritic cell. Incertain embodiments, the dendritic cell is a mature dendritic cellobtained from a cell of cell line DCOne as deposited under theconditions of the Budapest treaty with the DSMZ under accession numberDSMZ ACC3189 on 15 Nov. 2012. The process of obtaining mature dendriticcells from the deposited DCOne cell line is for instance described inEP2931878B1.

As used herein, the term “about” or “approximately” when referring to ameasurable value, such as a distance from a tumor site, encompassesvariations of ±20% or ±10%, ±5%, ±1%, or ±0.1% of a given value orrange, as are appropriate to perform the methods disclosed herein.

Compositions and Formulations

As provided herein, a first aspect relates to a vaccination stepcomprising the administration of (vaccination with) a first composition(e.g., an immunogenic composition) comprising a non-tumor antigen (e.g.,a non-human antigenic polypeptide as an immunogen), or comprising anucleic acid encoding a non-tumor antigen (e.g., a nucleic acid encodinga non-human antigenic polypeptide). In certain embodiments, the firstcomposition comprises a non-tumor antigen or a nucleic acid encoding anon-tumor antigen. In certain embodiments, the first compositionoptionally comprises one or more pharmaceutically-acceptable carriers,adjuvants, excipients and/or diluents.

As provided herein, a second aspect relates to a tumor-marking stepcomprising the administration of (vaccination with) a second composition(e.g., an immunogenic composition) comprising a non-tumor antigen (e.g.,a non-human antigenic polypeptide as an immunogen), or comprising anucleic acid encoding a non-tumor antigen (e.g., a nucleic acid encodinga non-human antigenic polypeptide). In certain embodiments, the secondcomposition comprises a non-tumor antigen or a nucleic acid encoding thenon-tumor antigen. In certain embodiments, the second compositionoptionally comprises one or more pharmaceutically-acceptable carriers,adjuvants, excipients and/or diluents.

In certain embodiments, the non-tumor antigen (e.g., non-human antigenicpolypeptide) as disclosed herein serves two purposes. The first purposeis in generating an immune response. In certain embodiments, the immuneresponse is a T-cell mediated immune response, against the antigen(e.g., non-human antigen, non-tumor antigen), by being incorporated inan immunogenic composition as an immunogen. The second purpose is inmarking a tumor as a target for said immune response. The skilled personwill directly understand that it is necessary that the tumor marking andmounting/generation of an immune response are matched in that themounted immune response is directed against the tumor thus marked.“Matched” means that the immune response (to be) elicited isspecifically directed against the antigenic polypeptide activelyintroduced into the tumor. In certain embodiments, the same or acorresponding antigenic epitope is used in marking the tumor and inelicitation of an immune response. Therefore, In certain embodiments,following the administration of a first composition (e.g., animmunogenic composition) as described herein to a subject, an immuneresponse is elicited that is specifically directed against a tumor thatis to be marked (or a tumor that is already marked) as a target for animmune response based on the same antigen.

In other words, the antigenic polypeptide in the second composition formarking, and the antigenic polypeptide in the first composition arematched, in that the immune response that is elicited followingadministration of the first composition to a subject is directed againsta tumor marked with said antigenic polypeptide following intratumoraldelivery of the same, or at least immunogenically the same, antigenicpolypeptide. This may mean that the immune response elicited followingadministration of an immunogenic composition as described herein, isspecifically directed to at least one T-cell epitope and/or B-cellepitope with which the tumor is to be marked (or is marked). In certainembodiments, the non-human antigenic polypeptide in said immunogeniccomposition is a polypeptide corresponding to the polypeptide used fortumor marking as described herein.

In certain embodiments, the immune response elicited followingadministration of a first composition (e.g., an immunogenic composition)as described herein, is a T-cell mediated immune response or aT-cell-dependent immune response. It is within the skilled person'scapabilities to identify appropriate immunogens and/or adjuvants thatactivate the cellular arm of immunity. References that aid the skilledperson in selecting appropriate antigens are for instance Bender et al.,J. Exp. Med, 182:1663-1671 (1995); Bennett et al., Nature, 393:478-480(1998); Kalinski and Moser, Nature, 5:251-260 (2005); Van Tenderloo etal., PNAS, 107:31, p. 13824-13829 (2010); Anguille et al., Blood, 12;130(15):1713-1721 (2017); Tacken et al., Blood, 106:4, p. 1278-1285(2005); Vigneron et al, Cancer Immunity, 13:15 (2013); and Cheever etal, Clin Cancer Res; 15:5323-5337 (2009), all of which are incorporatedby reference herein in their entirety. The skilled person directlyunderstands that antigenic polypeptides described in relation toimmunogenic compositions stand also in relation to intratumoral deliveryaspects, and vice versa. Examples of suitable antigens include proteinsof viral, bacterial, fungal origin; allergens, toxins and venoms, ormodel antigens of various sources such as chicken egg ovalbumin andkeyhole limpet hemocyanin from the giant keyhole limpet, Megathuracrenulata. In certain embodiments, a suitable antigen is of bacterialorigin. In certain embodiments, a suitable antigen is a diphtheriatoxin. In certain embodiments, a suitable antigen is a non-toxic variantof diphtheria toxin. In certain embodiments, a suitable antigen isCRM197. Other suitable antigenic polypeptides are polypeptides employedin a prior vaccination of a subject, such as recall antigens, which aredescribed in more detail herein below. Common vaccines, used in suchvaccinations, may include different antigenic polypeptides, which can bemultivalent in that they comprise different microbial (recall) antigenswith or without adjuvants.

The term “recall antigen,” as used herein, refers to an antigen (e.g.,antigenic polypeptide) which has previously (e.g., prior to theoccurrence of a tumor in the subject or prior to a tumor-marking step)been encountered by a subject. Recall antigens are those which havepreviously been encountered by the subject and for which there existspre-existing memory lymphocytes in the subject. In certain embodiments,a recall antigen refers to an antigen (e.g., antigenic polypeptide) forwhich pre-existing memory lymphocytes exist in the subject, e.g., as aresult of prior infections or vaccinations. In certain embodiments, arecall antigen refers to an antigenic polypeptide which has previouslybeen encountered by a subject via vaccination. In certain embodiments,the recall antigen is an antigenic polypeptide for which there ispre-existing immunity in said subject.

The skilled person has multiple methods and means at his disposal thathe can routinely apply in order to provide mounting of an immuneresponse against a non-human antigenic polypeptide as an immunogencomprised in an immunogenic composition as described herein.

References that aid the skilled person in selecting adjuvants thatdirect the immune response towards cellular immunity are for instancePashine et al., Nature Medicine Supplement, 11: S63-S68 (2005) and Awateet al., Frontiers in Immunology, 4:114, p. 1-10 (2013), the disclosuresof which are incorporated by reference herein in their entirety.Examples of such adjuvants are aluminum mineral salts, oil-in-wateremulsions, liposomes, toll-like receptor agonists or combinationsthereof. Other adjuvants include liposomes, virosomes, MF59, Montanide,ISCOMs, QS-21, aluminum, ASO4, Poly I:C, MPL, GLA, imiquimod, CpG ODN,chitin, chitosan, β-glucan, or combinations thereof. (Temizoz et al. IntImmunol. 2016 July; 28(7): 329-338, the disclosure of which isincorporated by reference herein in its entirety).

In certain embodiments, compositions (e.g., a first compositioncomprising a non-tumor antigen and a second composition comprising thesame non-tumor antigen) for use according to methods as described hereinoptionally comprise: a dendritic cell comprising the non-tumor antigen;a T-cell immune response-eliciting adjuvant; a T-cell immuneresponse-eliciting virus or a virus-like particle comprising thenon-tumor antigen or a nucleic acid encoding the non-tumor antigen; or acombination thereof.

In general, it is explicitly envisaged herein that embodiments thatrelate to the compositions for use in a method as described herein, alsoapply to aspects for instance the (i) non-tumor antigen (e.g., non-humanantigenic polypeptide), or nucleic acid encoding the same for use in amethod as described herein, (ii) immunogenic composition for use in amethod as described herein, (iii) a method for eliciting an immuneresponse, (iv) a method of treatment, and other aspects for use in amethod as described herein where appropriate.

In certain embodiments, a method of the present disclosure employs theuse of a first composition and a second composition. In certainembodiments, the first composition comprises an antigenic polypeptide(e.g., a non-tumor antigen) or a nucleic acid encoding an antigenicpolypeptide. In certain embodiments, the first composition comprises anantigenic polypeptide. In certain embodiments, the first compositioncomprises a nucleic acid encoding an antigenic polypeptide. In certainembodiments, the first composition comprises a non-tumor antigen. Incertain embodiments, the first composition comprises a nucleic acidencoding a non-tumor antigen.

In certain embodiments, the second composition comprises an antigenicpolypeptide (e.g., a non-tumor antigen) or a nucleic acid encoding anantigenic polypeptide (i.e., the second composition comprises anantigenic polypeptide or a nucleic acid encoding the antigenicpolypeptide which is the same as the antigenic polypeptide as in thefirst composition, or at least, immunologically the same antigenicpolypeptide as in the first composition). In certain embodiments, thesecond composition comprises an antigenic polypeptide. In certainembodiments, the second composition comprises a nucleic acid encodingthe antigenic polypeptide. In certain embodiments, the secondcomposition comprises a non-tumor antigen. In certain embodiments, thesecond composition comprises a nucleic acid encoding a non-tumorantigen.

In certain embodiments, the first composition and/or the secondcomposition may comprise a dendritic cell comprising an antigenicpolypeptide (e.g., a non-tumor antigen) or a nucleic acid encoding anantigenic polypeptide. In certain embodiments, the first compositioncomprises a dendritic cell comprising an antigenic polypeptide or anucleic acid encoding an antigenic polypeptide. In certain embodiments,the second composition comprises a dendritic cell comprising anantigenic polypeptide or a nucleic acid encoding an antigenicpolypeptide. In certain embodiments, the first composition comprises adendritic cell comprising a non-tumor antigen or a nucleic acid encodinga non-tumor antigen. In certain embodiments, the second compositioncomprises a dendritic cell comprising a non-tumor antigen or a nucleicacid encoding the non-tumor antigen.

In certain embodiments, the dendritic cell is employed as a dendriticcell vaccine, provided that such cells are loaded with the antigenicpolypeptide as described herein. In certain embodiments, a composition(e.g., a first composition or a second composition) comprises a maturedendritic cell differentiated from a precursor cell line. In certainembodiments, a composition (e.g., a first composition or a secondcomposition) comprises a mature dendritic cell that is CD34-positive,CD1a-positive, and CD83-positive. In certain embodiments, the dendriticcell is a cell of cell line DCOne as deposited at the DSMZ underaccession number DSMZ ACC3189 on 15 Nov. 2012. See, e.g., WO2014/006058, the disclosure of which is incorporated by reference hereinin its entirety For example, in certain embodiments, the firstcomposition and/or the second composition each comprise a dendritic cellof cell line DCOne comprising an antigenic polypeptide (e.g., anon-tumor antigen) or a nucleic acid encoding the antigenic polypeptide.Loading strategies for dendritic cells are discussed herein. The skilledperson has ample guidance on how dendritic cells can be effectively usedin the form of immunogenic compositions, which is for instance describedin multiple references including EP2931878 B1, WO 2014/006058 A1, WO2009/019320 and Saxena and Bhardwaj, Trends in Cancer, 4:2, p. 119-137(2018), the disclosures of which are incorporated by reference herein intheir entirety.

In certain embodiments, a pharmaceutically effective amount of acomposition is administered. As used herein, an “effective amount” or a“pharmaceutically effective amount” of, e.g., a first composition or asecond composition, refers to an amount effective, at dosages and forperiods of time necessary to achieve an immune response. For example, aneffective amount is sufficient to induce an immune response against anantigenic polypeptide (e.g., non-tumor antigen), optionally comprised ina dendritic cell. An effective amount is sufficient to induce an immuneresponse against a tumor that has been marked using an antigenicpolypeptide (e.g., non-tumor antigen) as described herein.

A first composition and/or a second composition as described herein maycomprise any adjuvant known to those in the art. Adjuvants known in theart, regardless of the route of administration, may be employed toimprove/enhance the immunogenicity of an antigenic polypeptide (e.g., anon-tumor antigen) comprised within a composition of the presentdisclosure. Adjuvants enhance the immunogenicity of an antigen (e.g., acomposition comprising a non-tumor antigen) but are not necessarilyimmunogenic themselves.

Adjuvants have been used by those of skill in the art to improve immuneresponses to, e.g., vaccines. Adjuvants may be intrinsic or extrinsic.Intrinsic adjuvants may be derived from killed or attenuated bacteriaused as vaccines. Extrinsic adjuvants maybe an immune modulatingsubstance non-covalently linked to antigens and are formulated toenhance immune responses.

In certain embodiments, the first composition and/or the secondcomposition may comprise a T-cell immune response-eliciting adjuvant.The term “T-cell immune response-eliciting,” as used in relation toadjuvants or virus or virus-like particles herein, refers to enhancingCD4+ and/or CD8+ T-cell immune responses or driving the immune responsetowards CD4+ and/or CD8+ T-cell activation. The skilled person is wellaware of adjuvants that can be employed for this purpose, such asliposomes, virosomes, MF59, Montanide, ISCOMs, QS-21, aluminum, ASO4,Poly I:C, MPL, GLA, imiquimod, CpG ODN, chitin, chitosan, β-glucan, orcombinations thereof. (Temizoz et al. Int Immunol. 2016 July; 28(7):329-338, the disclosure of which is incorporated by reference herein inits entirety).

In certain embodiments, adjuvants may be used specifically forparenteral modes of administration. Such adjuvants include, e.g.,aluminum compounds (such as aluminum phosphate and aluminum hydroxide).The antigen can be precipitated with, or adsorbed onto, an aluminumcompound according to standard protocols. Other adjuvants for parenteralmodes of administration, as well as intratumoral or peri-tumoral modesof administration, are known to those of skill in the art.

A first composition and/or a second composition as described herein maycomprise a virus, for example, a T-cell immune response-eliciting virus,or a virus-like particle (VLP), comprising an antigenic polypeptide(e.g., non-tumor antigen) or a nucleic acid encoding the antigenicpolypeptide. It is within routine experimentation to design and producea virus or VLP that can be employed in, or as a composition as describedherein. Such viruses, especially T-cell immune response-elicitingviruses or VLPs, have been described extensively for vaccinationpurposes. This follows for instance from Frietze et al., Curr OpinVirol., 18: 44-49 (2016); Koup and Douek, Cold Spring Harb Perspect Med,2011; 1: a007252, the disclosures of which are incorporated by referenceherein in their entireties. Examples of T-cell immune response-elicitingviruses or VLPs are for instance cowpox (vaccinia) viruses orderivatives thereof such as modified vaccinia virus Ankara (MVA),adenovirus or adeno-associated viruses and VLP's based on humanpapillomavirus, hepatitis B virus or VLP's engineered to presentdifferent tumor antigens. In certain embodiments, a composition asdescribed herein (e.g., the second composition used in a tumor markingstep) may comprise an oncolytic virus. Viruses that have been clinicallytested to be oncolytic include, without limitation, adenovirus,reovirus, measles, herpes simplex, Newcastle disease virus, andvaccinia.

As used herein, the term “pharmaceutical composition” or “pharmaceuticalformulation” refers to a preparation which is in such form as to permitthe biological activity of an active ingredient contained therein to beeffective (e.g., permit an antigenic polypeptide contained therein to beimmunogenic), and which contains no additional unacceptably toxiccomponents, with respect to toxicity when administered to a subject. A“pharmaceutically acceptable carrier” refers to an ingredient in apharmaceutical formulation and/or composition, other than an activeingredient, which is nontoxic to a subject. Pharmaceutically acceptablecarriers include, without limitation, a stabilizer, excipient, buffer,or preservative. In certain embodiments, the choice of carrier isdetermined in part by the particular method of administration.Accordingly, there are a variety of suitable formulations andcompositions. Various formulations and compositions are known in the artthat are suitable for, e.g., intratumoral administration, intramuscularadministration, and other routes of administration.

In certain embodiments, the pharmaceutical composition can containpreservatives. Suitable preservatives may include, e.g., propylparaben,methylparaben, benzalkonium chloride, and sodium benzoate. In certainembodiments, a mixture of two or more preservatives is used. Thepreservative or mixtures thereof are typically present in an amount ofabout 0.0001% to about 2% by weight of the total composition.

Carriers are further described, e.g., by Remington's PharmaceuticalSciences 16th edition, Osol, A. Ed. (1980). Pharmaceutically acceptablecarriers are generally nontoxic to subjects administered compositionsaccording to methods described herein at the dosages and concentrationsemployed, and include, but are not limited to: buffers such as citrate,phosphate, and other organic acids; antioxidants including methionineand ascorbic acid; low molecular weight (less than about 10 residues)polypeptides; hydrophilic polymers such as polyvinylpyrrolidone;proteins, such as gelatin, immunoglobulins, or serum albumin;preservatives (such as benzalkonium chloride; benzethonium chloride;phenol, butyl or benzyl alcohol; octadecyldimethylbenzyl ammoniumchloride; alkyl parabens such as methyl or propyl paraben; catechol;resorcinol; hexamethonium chloride; 3-pentanol; cyclohexanol; andm-cresol); amino acids such as glutamine, asparagine, histidine,glycine, arginine, or lysine; monosaccharides, disaccharides, and othercarbohydrates including dextrins, glucose, or mannose; sugars such assucrose, trehalose, sorbitol, or mannitol; salt-forming counter-ionssuch as sodium; metal complexes (e.g., Zn-protein complexes); non-ionicsurfactants such as polyethylene glycol (PEG); and/or chelating agentssuch as EDTA.

In certain embodiments, buffering agents are included in thecompositions. Suitable buffering agents include, for example, sodiumcitrate, citric acid, potassium phosphate, phosphoric acid, and variousother acids and salts. In certain embodiments, a mixture of two or morebuffering agents is used. The buffering agent or mixtures thereof aretypically present in an amount of about 0.001% to about 4% by weight ofthe total composition. Methods for preparing administrablepharmaceutical compositions are known to those in the art. See, e.g.,Remington: The Science and Practice of Pharmacy, Lippincott Williams &Wilkins; 21st ed. (May 1, 2005).

In certain embodiments, the compositions and formulations describedherein can include aqueous solutions. The formulation or composition mayalso contain more than one active ingredient useful for the particularindication, disease, or condition (e.g., tumor type) being treated usinga method as described herein. Such active ingredients are suitablypresent in combination in amounts that are effective for the purposeintended.

Formulations and compositions include those for oral, intravenous,intraperitoneal, subcutaneous, pulmonary, transdermal, intramuscular,intranasal, buccal, sublingual, or suppository administration.Formulations and compositions include those for any one of variousroutes of administration known in the art to those of skill in the art.In certain embodiments, the compositions are administered parenterally.The term “parenteral,” as used herein, includes intravenous,intramuscular, subcutaneous, rectal, vaginal, and intraperitonealadministration.

In certain embodiments, compositions and formulations are provided assterile liquid preparations, e.g., suspensions, emulsions, dispersions,viscous compositions, or isotonic aqueous solutions, which may in someembodiments be buffered to a selected pH. In certain embodiments,compositions and formulations are provided as gels, other viscouscompositions, and solid compositions. Viscous compositions, can beformulated within the appropriate viscosity range to provide longercontact periods with specific tissues. Liquid or viscous compositionscan comprise carriers, which can be a solvent or dispersing mediumcontaining, e.g., saline, phosphate buffered saline, water, polyol(e.g., propylene glycol, liquid polyethylene glycol, glycerol) andsuitable mixtures thereof.

Sterile injectable solutions can be prepared by incorporating into thecompositions a solvent, such as in admixture with a suitable carrier,diluent, or excipient such as sterile water, physiological saline,glucose, dextrose, or the like. The compositions can contain gelling orviscosity enhancing additives, pH buffering agents, auxiliary substancessuch as wetting, dispersing, or emulsifying agents (e.g.,methylcellulose), flavoring agents, colors, and/or preservatives,depending upon the route of administration and the preparation desired.Standard texts available to those having knowledge in the art may insome aspects be consulted to prepare suitable preparations.

Various additives which enhance the sterility and stability of thecompositions, can be added, including without limitation chelatingagents, antimicrobial preservatives, buffers, and antioxidants.Compositions can be kept sterile from or of the action of microorganismsby various antibacterial and antifungal agents, e.g., chlorobutanol,parabens, phenol, and sorbic acid. Prolonged absorption of theinjectable pharmaceutical form can be brought about by the use of agentsdelaying absorption, for example, aluminum monostearate and gelatin.

The skilled person is aware of other suitable immunogenic compositionsthat mount an immune response against an antigen as described herein.For instance, other options involve the use of a subunit vaccinecomprising an immunogen as described herein, and carrier proteinscoupled to an immunogen.

Antigenic Polypeptides and Nucleic Acids

In certain embodiments, a composition for use in a method as describedherein comprises an antigenic polypeptide (e.g., a non-tumor antigen),or a nucleic acid encoding the antigenic polypeptide. In certainembodiments, where the antigenic polypeptide is in a composition forintratumoral administration, the antigenic polypeptide is tumor-targetedor prepared for intratumoral delivery, or the nucleic acid encoding theantigenic polypeptide, is either tumor-targeted or is prepared forintratumoral administration. The skilled person will understand that thenew concept of tumor antigen-independent vaccination can be realizedwith multiple methods and means known in the art, both with regard tothe marking of a tumor, as well as with the vaccination that mounts animmune response against a marked tumor as already described.

In the medical methods described herein, marking or labelling of a tumoras a target for an immune response by employing a non-human antigenicpolypeptide as described herein, occurs in vivo, not in vitro or exvivo.

More specifically, the antigenic polypeptide or nucleic acid asdescribed herein can be prepared for intratumoral delivery in a varietyof ways, generally well known in the art. For instance, preparing mayinvolve tumor-targeting of said polypeptide or nucleic acid, e.g., bypreparing a tumor-targeting composition comprising said polypeptide ornucleic acid. A tumor-targeting composition comprises the polypeptide ornucleic acid in such a way that it is rendered tumor-specific. Incertain embodiments, upon administration of a tumor-targeted polypeptideor nucleic acid to a subject, intratumoral delivery is effectuated onthe basis of specificity for tumor tissue as compared to non-tumortissue. Tumor specificity also indicates that it may allow for homing toa tumor so as to provide for intratumoral delivery.

In certain embodiments, the polypeptide prepared for intratumoraldelivery, or the nucleic acid encoding said polypeptide, istumor-targeted by using one or more of, e.g., a tumor-specific virus,including an oncolytic virus, comprising a nucleic acid encoding saidpolypeptide; a tumor-specific nanoparticle comprising said polypeptideor a nucleic acid encoding said polypeptide. In certain embodiments,said polypeptide or nucleic acid is tumor-targeted by using atumor-targeting antibody, peptide, small molecule, or nucleic acidaptamer fused to said polypeptide or nucleic acid.

Another way of tumor-targeting a polypeptide or nucleic acid asdescribed herein (so as to effectuate intratumoral delivery uponadministration to a subject) involves the preparation of an oncolyticvirus that comprises a nucleic acid encoding an antigenic polypeptide asdescribed herein, which is engineered to express said nucleic acid intoa tumor cell. That oncolytic viruses can be used to specifically targettumor cells is extensively described in the art, for instance in Lawleret al., JAMA Oncol. 1; 3(6):841-849 (2017); Howells et al., Front Oncol.7:195 (2017), the disclosures of which are incorporated by referenceherein in their entireties. In addition, as exemplified in for instanceWO2014138314 A1 (the disclosure of which is incorporated by referenceherein in its entirety), oncolytic viruses can be modified to engagetumor cells. It is also well-known in the art that oncolytic viruses canbe used to deliver a nucleic acid construct encoding a polypeptide intoa tumor cell, said virus being engineered to express said polypeptideinto a tumor cell (Hutzler et al., Scientific Reports, 7: 16892 (2017);Grossardt et al., Human Gene Therapy, 24:644-654 (2013); Andtbacka etal., Journal of Clinical Oncology, 22:25, p. 2780-2788 (2015), thedisclosures of which are incorporated by reference herein in theirentireties). Subsequent intracellular processing of said polypeptide andantigen-presentation by said tumor cell provide for a tumor marked withan antigenic polypeptide as described herein. In other words, and incertain embodiments, following intratumoral delivery an antigenicpolypeptide as described herein is presented by the MHC system of atumor cell upon expression of said nucleic acid as described herein in acell of said tumor to thereby mark said tumor as a target for an immuneresponse.

Examples of oncolytic viruses that can be used for tumor-targeting areAdenovirus, Herpes simplex virus, Pox virus, Coxsackie virus, Marabavirus, Poliovirus, Measles virus, Newcastle Disease virus (Lal andRajala, Cancer Gene Therapy, DOI 10.1038/s41417-018-0018-1 (2018);Haddad, Frontiers in Immunology, 7:96 (2017); Bommareddy et al., NatureReviews Immunology (2018), the disclosures of which are incorporated byreference herein in their entireties).

A tumor-specific virus such as an oncolytic virus may be prepared in apharmaceutical formulation adapted for parenteral administration. Such aformulation generally comprises a carrier such as for instance anaqueous or oily solution, dispersion, emulsion and/or suspension.Parenteral administration involves the injection or infusion into a bodytissue or body fluid, whereby in certain embodiments, a syringe, needle,or catheter is used. In certain embodiments, the carrier is an aqueoussolution, and in certain embodiments, distilled sterile water, saline,buffered saline, or another pharmaceutically acceptable excipient forinjection. Examples of parenteral modes of administration areintravenous, intra-arterial, intra-peritoneal, subcutaneous,intramuscular and intratumoral administration, which are well known tothe person skilled in the art. In certain embodiments, a mode ofadministration of a tumor-specific virus such as an oncolytic virus isintravenous or intratumoral administration (Marelli et al., Frontiers inImmunology, 9:866 (2018), the disclosure of which is incorporated byreference herein in its entirety).

The dose to be administered of a tumor-specific virus such as anoncolytic virus is a pharmaceutically effective dose, i.e., a dosesufficient to deliver an antigenic polypeptide or nucleic acid asdescribed herein into a tumor. It is routine practice to determine adosing regimen for a tumor-specific virus.

An alternative way of tumor-targeting a polypeptide or nucleic acid asdescribed herein (so as to effectuate intratumoral delivery uponadministration to a subject), involves the preparation of atumor-specific nanoparticle comprising an antigenic polypeptide ornucleic acid as described herein, the latter being engineered to expresssaid nucleic acid in a tumor cell after delivery. In the field of cancertherapy, it is well known that a nanoparticle, which comprises ananocarrier loaded or combined with for instance a polypeptide ofinterest, are extensively described in relation tospecifically/selectively targeting (homing to) tumor cells and tosubsequently deliver for instance a medicament such as a polypeptide tosaid tumor cell. Methods and means for tumor-targeting of nanoparticlesor nanocarriers is generally known and is inter alia described inOlusanya et al., Molecules 23:907 (2018); Din et al., Int JNanomedicine, 12:7291-7309 (2017); Alibakhshi et al., J Control Release,268:323-334 (2017); and US 2013/0330399 A1, the disclosures of which areincorporated by reference herein in their entireties. In certainembodiments, tumor-specific delivery methods including, withoutlimitation, use of nanoparticles, use of liposomes, and use ofphotochemical processes (e.g., photochemical internalization) may beused to enhance the delivery of an antigen (e.g., an antigenicpolypeptide (e.g., a non-tumor antigen), or a nucleic acid encoding theantigenic polypeptide) into the cytosol of a tumor cell.

Photochemical internalization refers to a delivery method which involvesthe use of light and a photosensitizing agent for introducing otherwisemembrane-impermeable molecules into the cytosol of a target cell, butwhich does not necessarily result in destruction or death of the targetcell. In this method, the molecule to be internalized or transferred isapplied to the cells in combination with a photosensitizing agent.Exposure of the cells to light of a suitable wavelength activates thephotosensitizing agent which in turn leads to disruption of theintracellular compartment membranes and the subsequent release of themolecule into the cytosol. In photochemical internalization, theinteraction between the photosensitizing agent and light is used toaffect the cell such that intracellular uptake of the molecule isimproved. Photochemical internalization as well as variousphotosensitizing agents are described in PCT Publication Nos. WO96/07432, WO 00/54708, WO 01/18636, WO 02/44396, WO 02/44395, and WO03/020309, U.S. Pat. Nos. 6,680,301, 5,876,989, the disclosures of whichare incorporated by reference herein in their entireties. In certainembodiments, photochemical internalization is used to deliver an antigeninto the cytosol of a tumor cell. In certain embodiments, photochemicalinternalization is used to enhance the delivery of an antigen into thecytosol of a tumor cell.

The nanoparticle, or nanocarrier as main part of the nanoparticle, canbe a polymeric nanoparticle, a micelle, a liposome, a nanogel or acarbon nanotube. Such a particle or carrier can be loaded with acompound of interest (such as a polypeptide) and actively targeted to atumor by decorating such a particle or carrier with for instanceantibodies or antibody fragments specific for a tumor antigen expressedon the surface of a tumor cell (see also the aforementioned references).Tumor-targeting moieties for a nanoparticle can in principle be anybiological or chemical structure that displays affinity for a moleculeexpressed on a tumor cell, such as a peptide, oligopeptide orpolypeptide, a protein, a hormone, a vitamin, an enzyme, a ligand of atumor antigen or an antibody or antibody fragment that specificallybinds to a tumor antigen. In certain embodiments, after administrationof a tumor-targeted nanoparticle and subsequent homing and binding to atumor cell, receptor-mediated endocytosis (internalization) allows foruptake of a nanocarrier by a tumor cell, thereby providing intracellulardelivery of for instance a polypeptide of interest, which can beintracellularly processed and subsequently presented as an antigen in anMHC complex by a tumor cell.

Alternatively, after administration of a tumor-targeted nanoparticle andsubsequent homing to a tumor and binding to a non-tumorous cell in thetumor, including an immune cell, such as a phagocytic cell orfibroblast, receptor-mediated endocytosis (internalization) allows foruptake of a nanocarrier by said cell, thereby providing intracellulardelivery of for instance a polypeptide of interest in a tumor, which canbe intracellularly processed and subsequently presented as an antigen inan MHC complex by said cell in said tumor. Specific examples oftumor-specific (or tumor-targeted) nanoparticles that can be employedfor intratumoral delivery of an antigenic polypeptide or nucleic acid asdescribed herein, are for instance poly(propylene) sulfide (PPS)nanoparticles, gold nanoparticles, PLGA nanoparticles, artificialexosomes, micelles or dendrimers.

In certain embodiments, a tumor-specific nanoparticle as describedherein is prepared in a pharmaceutical formulation adapted forparenteral administration. Such a formulation generally comprises acarrier such as for instance an aqueous or oily solution, dispersion,emulsion and/or suspension. Parenteral administration involves theinjection or infusion into a body tissue or body fluid, whereby in somecases, a syringe, needle, or catheter is used. In certain embodiments,the carrier is an aqueous solution, and in certain embodiments, thecarrier is distilled sterile water, saline, buffered saline, or anotherpharmaceutically acceptable excipient for injection. Examples ofparenteral modes of administration are intravenous, intra-arterial,intra-peritoneal, subcutaneous, intramuscular and intratumoraladministration, which are well known to the person skilled in the art.In certain embodiments, a mode of administration of a tumor-specificnanoparticle is intravenous or intratumoral administration.

The dose of tumor-specific nanoparticle to be administered is apharmaceutically effective dose, i.e., a dose sufficient to deliver anantigenic polypeptide or nucleic acid as described herein into a tumor.For a skilled person, it is routine practice to determine a dosingregimen for a tumor-specific nanoparticle.

In embodiments where the antigenic polypeptide or the nucleic acid asdescribed herein is not tumor-targeted, they are prepared forintratumoral delivery by being in a form that allows for intratumoralinjection. The skilled person directly understands that tumor-targetedcompositions as described herein can also be administeredintratumorally. The skilled person is aware of pharmaceuticalformulations that are adapted for intratumoral injection, which maycomprise a carrier such as for instance an aqueous or oily solution,dispersion, emulsion and/or suspensions. In embodiments where theantigenic polypeptide or nucleic acid as described herein are nottumor-targeted, the antigenic polypeptide and/or nucleic acid are, Incertain embodiments, comprised in a dendritic cell, or the antigenicpolypeptide is in an aqueous suspension or solution. In the same manner,in embodiments where the antigenic polypeptide or nucleic acid asdescribed herein are not tumor-targeted, the antigenic polypeptideand/or nucleic acid can be comprised in a virus. It is thus explicitlyenvisaged herein that marking of a tumor with an antigenic polypeptidecan occur at a tumor cell, but does not necessarily requireintracellular processing and antigen presentation by a tumor cellitself. For instance, such intracellular processing can also beeffectuated by other cell types in the tumor, including immune cellssuch as phagocytic cells—of which macrophages are an example—orfibroblasts. When dendritic cells are employed for tumor marking,marking of a tumor can be performed by antigen processing through theMHC system of the dendritic cell itself which dendritic cell isintratumorally injected. It is also known that dendritic cells, inparticular allogeneic dendritic cells, may attract endogenous immunecells including NK cells and cross-prime dendritic cells which enforcesthe immune response in the tumor (Laurell et al. 2017, J for Immunother.Of Cancer 5: 52, the disclosures of which is incorporated by referenceherein in its entirety).

Without being bound by theory, recruitment of previously ‘untouched’immune cells into the tumor, or using pre-existing immunity that was,before tumor marking, not directed against a tumor, breaks immunetolerance resulting in further recruitment of immune cells directedagainst, i.e., tumor antigens of the tumor.

With regard to tumor marking, the skilled person is well aware ofmethods and means relating to loading of dendritic cells with anantigenic polypeptide or with a nucleic acid, such as mRNA, encodingsuch a polypeptide. See for instance Van Nuffel et al., ISBT ScienceSeries, 8, 161-164 (2013); WO 2014/006058 A1; WO 2009/034172 A1, thedisclosures of which are incorporated by reference herein in theirentireties. In addition, the skilled person is well aware of methods andmeans for intratumoral injection of dendritic cells. See for instance US2004/0057935 A1; Cripe et al., Molecular Therapy, 23: 3, p. 602-608(2015); Hirooka et al., Oncotarget, 9:2, p. 2838-2847 (2018); Triozzi etal., Cancer, 89:12, p. 2646-2654 (2000); Laurell et al., Journal forImmunoTherapy of Cancer, 5:52 (2017), the disclosures of which areincorporated by reference herein in their entireties. In certainembodiments, said polypeptide prepared for intratumoral delivery, orsaid nucleic acid encoding said polypeptide, is for intratumoraladministration and is in the form of a dendritic cell. In certainembodiments, the dendritic cell is a (mature) dendritic cell obtainedfrom a cell of cell line DCOne as described herein, comprising saidpolypeptide or said nucleic acid encoding said polypeptide as describedherein. A person skilled in the art can routinely define a dosingregimen that suits intratumoral administration of a dendritic cellcomprising an antigenic polypeptide or a nucleic acid encoding saidpolypeptide (such as an mRNA) as described herein. The same applies toan aqueous suspension or solution comprising an antigenic polypeptide asdescribed herein.

It is clear that tumor marking can be effectuated via multiple differentmethods and means, as long as the tumor is marked with an antigenicpolypeptide as described herein. For instance, tumor marking does nothave to be effectuated exclusively by intracellular processing ofantigenic polypeptides by tumor cells or other cell types in the tumor.It is also possible that the antigenic polypeptides prepared forintratumoral delivery are extracellular in the tumor and are thus notinternalized by cells in said tumor. The presence of an extracellularantigenic polypeptide in the tumor will attract immune cells activatedprior to marking by a vaccination step as described herein. In certainembodiments, such a vaccination step, and subsequent generation ofimmunity, is performed prior to tumor marking.

Further, the polypeptide, or nucleic acid encoding said polypeptide,prepared for intratumoral delivery are, in certain embodiments,accompanied by immuno-modulatory compounds, such as a chemokine and/orcytokine, that modulates the tumor, in certain embodiments, the tumorsite or TME, to increase susceptibility to an immune response, in somecases to convert at least partially an immuno-tolerant tumor environmentinto an immuno-sensitive tumor environment or to facilitate (optimal)T-cell functionality in the tumor site or TME. Such an immunomodulatorycompound is in some cases included in an tumor-specific virus,tumor-specific nano-particle, dendritic cell, or aqueous suspension orsolution as described herein, either in the form of a polypeptide, or asa nucleic acid encoding such an polypeptide. In certain embodiments,examples of such immunomodulatory compounds are e.g., GM-CSF, CCRS,XCL1, CCL20 and CCL21 (Mohan et al., Immunobiology, 223:477-485 (2018);He et al., Journal of Experimental & Clinical Cancer Research, 29:37(2010); Nguyen-Hoai et al., Cancer Gene Therapy, 19: 69-76 (2012), thedisclosures of which are incorporated by reference herein in theirentireties). Thus, for use in a method as described herein, saidantigenic polypeptide, or a nucleic acid encoding said polypeptide,prepared for intratumoral delivery is in a composition that alsocomprises an immuno-modulatory compound (such as an immuno-modulatorypolypeptide or a nucleic acid encoding said immuno-modulatorypolypeptide), that converts at least partially an immuno-tolerant tumorsite or TME into an immuno-sensitive tumor site or TME, and/orfacilitates T-cell functionality in the tumor site or TME. In certainembodiments, said immuno-modulatory compound is an immunomodulatorypolypeptide, or a nucleic acid encoding said immuno-modulatorypolypeptide. In certain embodiments, the immuno-modulatory polypeptideis, or encodes for, GM-CSF, CCRS, XCL1 or CCL20, human GM-CSF, CCRS,XCL1 or CCL20. In certain embodiments, such an immuno-modulatorycompound facilitates T-cell functionality in the tumor site or TME.

The term “immuno-tolerant TME,” or “immuno-tolerant tumor site” as usedherein, refers to a well-established phenomenon wherein the environmentwithin a tumor provides for tolerance of, or insensitivity to, anantitumor immune response. In certain embodiments, a tumor site or TMEis immuno-tolerant if it is more tolerant of, or more insensitive to, animmune response directed against a tumor in said TME, as compared to animmune response directed against a target in an environment outside saidtumor, such as for instance an environment in or near healthy cells orhealthy tissue.

The term “immuno-sensitive TME” or “immuno-sensitive tumor site,” asused herein, refers to a situation wherein a tumor is sensitive orsusceptible to an antitumor immune response.

With regard to the antigenic polypeptide for use in a method asdescribed herein, it is an embodiment of the present disclosure that thepolypeptide is not a tumor antigen. The term “tumor antigen,” as usedherein, includes both tumor associated antigens (TAAs) and tumorspecific antigens (TSAs), including tumor neo-antigens. A tumorassociated antigen is an antigen that is expressed on the surface of atumor cell in higher amounts than is observed on normal cells or anantigen that is expressed on normal cells during fetal development. Atumor specific antigen is an antigen that is unique to tumor cells andis not expressed on normal cells. The term tumor antigen includes TAAsor TSAs that have been already identified and those that have yet to beidentified.

Any antigenic polypeptide can be employed insofar it is immunogenic in ahuman subject. This includes both antigenic polypeptides of human andnon-human origin. Therefore, an antigenic polypeptide can be a human ornon-human antigenic polypeptide that is immunogenic in a human subject.In certain embodiments, the antigenic polypeptide is non-human. It isnonetheless explicitly envisaged herein that in aspects and/orembodiments that recite the term “non-human antigenic polypeptide,” thataspect or embodiment can be amended so as to refer to “human antigenicpolypeptide,” or the term “human antigenic polypeptide” can be added insuch aspects and/or embodiments. Human antigenic polypeptides that areimmunogenic in a human subject are for instance embryonic, ovarian ortestis polypeptides. This applies for instance to NY-ESO-1, WT-1 and theMAGE antigens (see for instance Cheever et al, Clin Cancer Res;15:5323-5337 (2009); Vigneron et al, Cancer Immunity, 13:15 (2013) thedisclosures of which are incorporated by reference herein in theirentireties).

In one aspect, it is provided that the non-human antigenic polypeptidesthat are to be employed as the immunogen and marker in aspects of amethod as described herein are not previously encountered by a subjectas part of an immune response against a tumor. As such, in certainembodiments, the antigenic polypeptides are non-tumor antigens. Incertain embodiments, the antigenic polypeptides are antigens that havenot previously been encountered by the immune system of the subject andto which a subject is thus immunologically naïve, or are antigenicpolypeptides previously encountered by a subject, but not as part of animmune response against a tumor, and in some cases for which protectiveimmunity (memory T-cells and/or B-cells) exists. The latter can behighly beneficial, since it is not necessary to mount a de novo immuneresponse, which takes time to mount, but instead taps into, orre-activates, existing immunity and directs it to a tumor according tothe principle mechanism of a method as described herein. Therefore, inone embodiment, an non-human antigenic polypeptide as described hereinis rarely if ever encountered (by the immune system) by a large portionof the human population intended for potential vaccination or is anantigenic polypeptide against which immunity pre-exists (is present in asubject), wherein said immunity is not directed against a tumor. Thelatter form of immunity can for instance be provided by a priorvaccination against an infectious disease earlier in life, includingvaccination against hepatitis, such as hepatitis A and/or B, diphtheria,tetanus, pertussis, influenza, Haemophilus influenzae type b, polio(poliomyelitis), measles, mumps, rubella, varicella, humanpapillomavirus, Streptococcus pneumoniae (pneumonia), Neisseriameningitides (meningitis) or rotaviruses (rotaviral infection).Explicitly envisaged herein as non-human antigenic polypeptides for useaccording to a method as described herein are immunogenic polypeptidesof one or more of hepatitis, including hepatitis A and/or B, diphtheria,tetanus, pertussis, influenza, Haemophilus influenzae type b, polio,measles, mumps, rubella, varicella, human papillomavirus, Streptococcuspneumoniae, Neisseria meningitides or rotaviruses. In certainembodiments, a non-human antigen polypeptide as described herein is amicrobial polypeptide employed in a prior vaccination of said subject.In certain embodiments, the prior vaccination was against an infectiousdisease. In certain embodiments, the prior vaccination was againsthepatitis A and/or B; diphtheria; tetanus; pertussis; influenza;Haemophilus influenzae type b; polio; measles; mumps; rubella;varicella; human papillomavirus, Streptococcus pneumoniae, Neisseriameningitides or rotaviruses. The skilled person understands that thepolypeptide employed in a prior vaccination could be administered indifferent forms, such as part of (i) subunit vaccine, (ii) inactivatedor attenuated micro-organism, (iii) toxoid vaccine (i.e., vaccinecomprising inactivated toxins), etc.

In certain embodiments, a non-human antigenic polypeptide as describedherein is a polypeptide selected from the group formed by VP3 fromhepatitis A virus, including VP3 as identified in UniProtKB Acc. No.P08617, last modified: Aug. 1, 1988—v1; tetanus toxin from Clostridiumtetani, including tetanus toxin as identified in UniProtKB Acc. No.P04958, last modified Jan. 23, 2007—v2; pertussis toxin from Bordetellapertussis, including pertussis toxin as identified in UniProtKB Acc. No.P04977, last modified: Aug. 13, 1987—v1; protein D from Haemophilusinfluenzae, including protein D as identified in UniprotKb Acc. No.R4R7Q5 (last modified: Jul. 24, 2013—v1); Vp1 capsid protein frompoliovirus, including Vp1 capsid protein as identified in UniProtKB Acc.No. P03300, last modified: Jan. 23, 2007—v3; hemagglutinin from measlesvirus, including hemagglutinin as identified in UniProtKB Acc. No.P08362, last modified Aug. 1, 1988—v1; nucleoprotein from mumps virus,including nucleoprotein as identified in UniProtKB Acc. No. Q771S8, lastmodified: Jul. 5, 2004—v1; glycoprotein E1 or E2 from rubella virus,including glycoprotein E1 or E2 as identified in UniprotKb Acc. No.P08563, last modified: May 30, 2006—v2; immediate early 62 (1E62)protein from varicella zoster virus, including 1E62 protein asidentified in UniprotKb Acc. No. P09310, last modified: Jul. 1, 1989—v1;E6 or E7 protein from HPV16 or HPV18, including E6 or E7 protein asidentified in UniprotKb Acc. Nos. P03126 (last modified: Jul. 21,1986-v1), P03129 (last modified: Jul. 21, 1986—v1), P06463 (lastmodified: Jan. 1, 1988—v1) or P06788 (last modified: Apr. 1, 1990—v2);Spr96/2021, PV7 (7-valent) and/or PV13 (13-valent), in some cases,derived from or based on Streptococcus pneumoniae; Neisseria heparinbinding antigen (NHBA), factor H binding protein (fHbp) or Neisserialadhesin A (nadA) from Neisseria meningitides, including NHBA asidentified in UniprotKb Acc. No. Q7WYZO (last modified: Oct. 1,2003—v1), fHbp as identified in UniprotKb Acc. No. B2CQ00 (last modifiedMay 20, 2008—v1) or nadA as identified in UniprotKb Acc. No. Q9K105(last modified Oct. 1, 2000—v1); VP8 or VP6 from rotaviruses, includingVP8 as identified in UniprotKb Acc. No. P12473 (last modified: Mar. 24,2009—v2) or VP6 as identified in UniprotKb Acc. No. P04509 (lastmodified: May 30, 2000—v2); and diphtheria toxin from Corynebacteriumdiphtheria, including a detoxified variant thereof referred to asCRM-197. It is noted that when reference is made to polypeptidesemployed in a prior vaccination, also included in said terminology aredetoxified and immunogenic variants or parts of said polypeptides. Incertain embodiments, an antigenic polypeptide as described herein is arecall antigen. In certain embodiments, an antigenic polypeptide asdescribed herein is a microbial recall antigen.

In certain embodiments, the antigenic polypeptide chosen is matched withexisting immunity (e.g., memory immunity in the form of memory T-cellsand/or B-cells) in a subject, such that vaccination with such anantigenic polypeptide as immunogen, and tumor marking with such anantigenic polypeptide, taps into said pre-existing immunity (i.e.,activates memory T-cells and/or B-cells to mount an immune responseagainst said tumor). The skilled person can easily establish whetherimmunity against an antigenic polypeptide exists. In certainembodiments, the pre-existing immunity was generated prior toestablishment of a tumor. In certain embodiments, the pre-existingimmunity was generated early in life of the subject, e.g., at a timebetween the age of 0-20 years, at a time between the age of 1-12 or 1-6years. In certain embodiments, the pre-existing immunity was generatedat a time between the age of about 0-1 years, about 0-2 years, about 0-3years, about 1-3 years, about 2-4 years, about 3-5 years, about 4-6years, about 5-7 years, about 6-8 years, about 7-9 years, about 8-10years, about 9-11 years, about 10-12 years, about 11-13 years, about12-14 years, about 13-15 years, about 14-16 years, about 15-17 years,about 16-18 years, about 17-19 years, about 18-20 years, at a timebefore the age of 1, at a time before the age of 2, at a time before theage of 3, at a time before the age of 4, at a time before the age of 5,at a time before the age of 6, at a time before the age of 7, at a timebefore the age of 8, at a time before the age of 9, at a time before theage of 10, at a time before the age of 11, at a time before the age of12, at a time before the age of 13, at a time before the age of 14, at atime before the age of 15, at a time before the age of 16, at a timebefore the age of 17, at a time before the age of 18, at a time beforethe age of 19, at a time before the age of 20, at a time before the ageof 25, at a time before the age of 30, at a time before the age of 35,at a time before the age of 40, at a time before the age of 45, at atime before the age of 50, at a time before the age of 60, at a timebefore the age of 70, at a time before the age of 80, at a time beforethe age of 90, at a time before the age of 100, or at a time during thelife of the subject.

In order to capitalize on pre-existing immunity, in certain embodiments,dormant immune cells are reactivated by at least one immunization withan immunogenic composition as described herein.

In certain embodiments, the antigenic polypeptide used in aspects of amethod as described herein is not previously encountered by a subject aspart of an immune response against a tumor, is (i) not (or rarely)encountered by a human subject as part of an immune response, or (ii) isencountered as part of an immune response, but not an immune responseagainst a tumor, and wherein protective immunity is present in asubject.

In certain embodiments, the antigenic polypeptide as described hereinmounts an immune response in cancer patients, e.g., patients sufferingfrom a tumor. In certain embodiments, the antigenic polypeptide mountsan immune response in at least 90% of the patients intended forpotential vaccination using a method as described herein. For example,the antigenic polypeptide mounts an immune response in at least 91%,92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% of the patients intendedfor potential vaccination using a method as described herein. The immuneresponse thus mounted in cancer patients can be a de novo response dueto the fact that the patients' immune system has not previouslyencountered this immunogen.

In certain exemplary embodiments, the antigenic polypeptide is anon-mammalian polypeptide, such as a microbial polypeptide, or asynthetic polypeptide. In certain exemplary embodiments, the antigenicpolypeptide is selected from the group formed by keyhole limpethemocyanin (KLH), green fluorescent protein (GFP) including enhancedgreen fluorescent protein (eGFP), luciferase, beta-galactosidase and adiphtheria toxin.

The term “microbial polypeptide,” as used herein, refers to apolypeptide of a micro-organism, which includes bacteria, archaea,protists, fungi, unicellular plants and viruses.

In certain embodiments, the antigenic polypeptide (e.g., non-humanantigenic polypeptide) is a bacterial polypeptide, a polypeptideoriginating from an organism of the Archaea domain, a fungal polypeptideor a viral polypeptide. In certain embodiments, the antigenicpolypeptide is a plant polypeptide. Also envisaged are a non-humanmammalian polypeptide such as a polypeptide of a non-human primate, arodent (e.g., mice and rats), a rabbit, a pig, a sheep, a goat, a cow, ahorse and a donkey, a birds (e.g., a chicken, a turkey, a duck, a gooseand the like). The antigenic polypeptide can also be a polypeptide of asnail or other mollusk, e.g., one of the genus of Megathura, orMegathura crenulata.

In certain embodiments, antigenic polypeptides that are not mammalianpolypeptides find certain use in a method as described herein, sincenon-mammalian antigenic polypeptides are more immunogenic than mammalianpolypeptides when administered to a human subject. Examples of suitablenon-mammalian antigenic polypeptides are for instance green fluorescentprotein (GFP) including enhanced green fluorescent protein (eGFP),luciferase and beta-galactosidase.

One example of an antigenic polypeptide is Keyhole Limpet Hemocyanin(KLH) of Megathura crenulata. KLH can be either KLH1 (amino acidsequence is provided in UniProtKB—Q53IP9, last modified: Feb. 19,2014—v2) or KLH2 (amino acid sequence is provided in UniProtKB—Q1MVA1,last modified: May 30, 2006—v1). KLH is an example of a highlyimmunogenic antigen, which has been widely used as a universal immunogenand vaccine carrier.

Another example of an antigenic polypeptide is a diphtheria toxin, whichterm includes detoxified variants thereof such as cross-reactingmaterial (CRM)-197. In certain embodiments, the antigenic polypeptide(e.g., non-tumor antigen) is CRM197. In certain embodiments, diphtheriatoxin has the amino acid sequence as indicated in SEQ ID NO:1. Incertain embodiments, a detoxified variant of diphtheria toxin isCRM-197, which has the amino acid sequence as indicated in SEQ ID NO:1,except for glycine (G) at amino acid residue position 52 beingsubstituted with glutamic acid (E). The term also includes variants ofdiphtheria toxin that have at least 90%, at least 95%, at least 96%, atleast 97%, at least 98%, or at least 99% sequence identity to SEQ IDNO:1 or to a part of SEQ ID NO:1 having a continuous stretch of least100, at least 200 or at least 300 amino acid residues. In certainembodiments, the continuous stretch is in—or is—the amino acid regionindicated by positions 1-385 of SEQ ID NO:1. Alternatively, suchvariants include proteins having the amino acid sequence of SEQ ID NO:1,except that 1-50, 1-20, or 1-10, amino acid residues are deleted,inserted or substituted. Such variants may exhibit antigenicity and/orimmunogenicity as described herein.

The term “% sequence identity” is defined herein as the percentage ofamino acids in an amino acid sequence that is identical with the aminoacids in an amino acid sequence of interest, after aligning thesequences and optionally introducing gaps, if necessary, to achieve themaximum percent sequence identity. Methods and computer programs foralignments are well known in the art. Sequence identity is calculatedover substantially the whole length, in some cases, the whole (full)length, of an amino acid sequence of interest. The skilled personunderstands that consecutive amino acid residues in one amino acidsequence are compared to consecutive amino acid residues in anotheramino acid sequence.

In certain embodiments, in methods as described herein whereindiphtheria toxin is employed for intratumoral delivery of an antigenicpolypeptide, the tumor is a tumor that expresses the HB-EGF receptor. Incertain embodiments, a tumor that expresses the HB-EGF receptor isselected from the group consisting of an ovarian tumor; a lung tumor; abladder tumor; a gastric tumor; a pancreatic tumor; a breast tumor; aliver tumor (e.g., hepatocellular carcinoma); a brain tumor (e.g.,glioblastoma, astrocytoma, brain stem glioma, mixed glioma,oligodendroglioma, optic nerve glioma, and other tumors that originatein the brain, e.g., anaplastic astrocytoma, fibrillary astrocytoma,pilocytic astrocytoma); a neuroblastoma; a lymphoma including Hodgkinlymphoma or non-Hodgkin lymphoma, a histiocytic lymphoma or anaplasticlarge cell lymphoma; and a leukemia (e.g., AML, CML or ALL). In certainembodiments, the tumor that expresses the HB-EGF receptor is a malignanttumor selected from the group formed by ovarian cancer; lung cancer;bladder cancer; gastric cancer; pancreatic cancer; breast cancer;hepatocellular carcinoma; brain cancer (e.g., glioblastoma);neuroblastoma; lymphoma including Hodgkin lymphoma or non-Hodgkinlymphoma, histiocytic lymphoma or anaplastic large cell lymphoma; andleukemia, e.g., AML, CML or ALL.

Also provided herein are nucleic acids encoding the antigenicpolypeptide as described herein. In certain embodiments, a nucleic acidencoding CRM197 for use in a method as described herein, is provided.

Amino acid sequences of proteins or polypeptides as described herein canbe produced by methods and means generally available in the art. Forinstance, the person skilled in the art will understand how to generatea DNA sequence that encodes a fusion protein as described herein and howto manufacture and isolate a nucleic acid molecule with said DNAsequence using generally known recombinant DNA techniques. In certainembodiments, the sequence of the nucleic acid molecule iscodon-optimized for expression in a host cell. In this way codons areused that are favored for high level expression in a specific host cell.In certain embodiments, nucleic acid molecules are inserted in anexpression vector using recombinant DNA techniques known by the personskilled in the art. Expression vectors direct the expression of a fusionprotein as described herein in a host cell. In certain embodiments,these expression vectors are replicable in a host cell, either asepisomes or as part of the chromosomal DNA. Further, in certainembodiments, the expression vector comprises (i) a strongpromoter/enhancer, such as the CMV or SV40 promoter, (ii) an optimaltranslation initiation sequence, such as a ribosomal binding site andstart codon, and/or a KOZAK consensus sequence and (iii) a transcriptiontermination sequence, including a poly(A) signal when the protein isexpressed in eukaryotic cells. Suitable expression vectors includeplasmids and viral vectors such as adenoviruses, adeno-associatedviruses and retroviruses. The person skilled in the art will understandthat the expression vector to be used is dependent on the host cell thatis used for expression of a recombinant protein. In certain embodiments,an expression vector is suited for expression of a nucleic acid in aprokaryotic cell including a bacterial cell, or in a eukaryotic hostcell, such as a yeast cell and a mammalian cell. A suitable example ismammalian expression vector pCMV4.

As an alternative, a nucleic acid molecule may be inserted in the genomeof a host cell. In certain embodiments, the insertion is at a locus orwithin a region that ensures expression of a nucleic acid molecule asdescribed herein in the host cell.

Suitable host cells include prokaryotic and eukaryotic cells, such asbacterial cells, yeast cells, insect cells, animal cells, mammaliancells, murine cells, rat cells, sheep cells, simian cells and humancells. Examples of suitable eukaryotic host cells include, but are notlimited to HEK 293 cells, the hamster cell line CHO and BHK-21; themurine host cells NIH3T3, NSO and C127; the simian host cells COS andVero; and the human host cells HeLa, PER.C6, U-937 and Hep G2. Suitablecells are available from public sources such as ATCC and LifeTechnologies. A number of transfection techniques are known in the art,see, e.g., Graham et al., 1973. Virology 52: 456; Green et al., 2012.“Molecular Cloning: A Laboratory Manual,” CSHL Press; Davis et al.,“Basic Methods in Molecular Biology,” 1986, Elsevier; and Chu et al.,1981. Gene 13: 197, the disclosures of which are incorporated byreference herein in their entireties. The person skilled in the art mayemploy techniques as described in these references to introduce one ormore exogenous nucleic acid molecules into suitable host cells. Anexample of a host cell for the production of a fusion protein asdescribed herein is a HEK 293 cell.

The antigenic polypeptide as described herein can also be a syntheticpolypeptide, e.g., a synthetic polypeptide that is designed foreliciting a strong cellular immune response upon administration to ahuman subject.

When the antigenic polypeptide is for administration as an immunogen, itmay comprise a further polypeptide or conjugation partner so as toenhance elicitation of an immune response. Thus, said immunogen can be afusion polypeptide comprising said antigenic polypeptide and forinstance a carrier protein.

Methods of Administration

Provided herein are methods for treating a tumor (e.g., a solid tumor)in a subject. Also provided are methods for generating an immuneresponse against a tumor in a subject. Such methods comprise avaccination step comprising distally administering a first composition,and a tumor-marking step comprising intratumorally or peri-tumorallyadministering a second composition. Such methods comprise a vaccinationstep comprising administering a first composition to the subject at asite distal to a tumor site, wherein the first composition comprises anon-tumor antigen or a nucleic acid encoding the non-tumor antigen; anda tumor-marking step comprising administering a second composition tothe subject at the tumor site, wherein the second composition comprisesthe non-tumor antigen or a nucleic acid encoding the non-tumor antigen.The first composition and the second composition are described elsewhereherein.

In certain embodiments, the vaccination step comprises administering thefirst composition to a site that is away from the tumor. In certainembodiments, the vaccination step comprises administering the firstcomposition to a site distal to the tumor. In certain embodiments,distal administration of an immunogenic composition (e.g., a firstcomposition) in a vaccination step as described herein is through theparenteral route, which includes intravenous, intra-arterial,subcutaneous, intradermal, intranodal, intralymphatic and intramuscularadministration, which are all well known to the person skilled in theart. In certain embodiments, distal administration of an immunogeniccomposition (e.g., a first composition) described herein is delivered bya mode selected from the group consisting of intramuscular injection,subcutaneous injection, intravenous injection, intraarterial injection,intraperitoneal injection, intrasternal injection, intradermalinjection, transcutaneous injection, transdermal injection, and deliveryto the interstitial space of a tissue

In certain embodiments, the vaccination step comprises administration ofthe first composition, wherein the administration is not intratumoral,but instead is extratumoral and is in some cases intramuscular,intradermal, intravenous, intranodal or intralymphatic, intradermal,intravenous or a combination thereof. In certain embodiments, thevaccination step comprising administering the first compositionintramuscularly at a site distal to the tumor site.

In certain embodiments, the vaccination step comprises distallyadministering the first composition at a site at least about 0.1 mm, atleast about 0.2 mm, at least about 0.3 mm, at least about 0.4 mm, atleast about 0.5 mm, at least about 0.6 mm, at least about 0.7 mm, atleast about 0.8 mm, at least about 0.9 mm, at least about 1 mm, at leastabout 2 mm, at least about 3 mm, at least about 4 mm, at least about 5mm, at least about 6 mm, at least about 7 mm, at least about 8 mm, atleast about 9 mm, at least about 10 mm, at least about 15 mm, at leastabout 20 mm, at least about 25 mm, at least about 30 mm, at least about35 mm, at least about 40 mm, at least about 45 mm, at least about 50 mm,at least about 60 mm, at least about 70 mm, at least about 80 mm, atleast about 90 mm, at least about 10 cm, at least about 20 cm, at leastabout 30 cm, at least about 40 cm, at least about 50 cm, 50 cm or moreaway from the tumor (e.g., the edge of the tumor, or the center of thetumor). In certain embodiments, the vaccination step comprisesadministering a first composition to the subject at a site distal to atumor site, therein the site distal to the tumor site is at least about0.1 mm, at least about 0.2 mm, at least about 0.3 mm, at least about 0.4mm, at least about 0.5 mm, at least about 0.6 mm, at least about 0.7 mm,at least about 0.8 mm, at least about 0.9 mm, at least about 1 mm, atleast about 2 mm, at least about 3 mm, at least about 4 mm, at leastabout 5 mm, at least about 6 mm, at least about 7 mm, at least about 8mm, at least about 9 mm, at least about 10 mm, at least about 15 mm, atleast about 20 mm, at least about 25 mm, at least about 30 mm, at leastabout 35 mm, at least about 40 mm, at least about 45 mm, at least about50 mm, at least about 60 mm, at least about 70 mm, at least about 80 mm,at least about 90 mm, at least about 10 cm, at least about 20 cm, atleast about 30 cm, at least about 40 cm, at least about 50 cm, 50 cm ormore away from the tumor (e.g., the edge of the tumor, or the center ofthe tumor).

In certain embodiments, the vaccination step comprises distallyadministering the first composition at a site in an organ system that isdifferent to the organ system in which the tumor resides. In certainembodiments, the vaccination step comprises administering a firstcomposition into an organ system that is different than the organ systemin which the tumor resides. For example, if the tumor resides at or inan ovary (e.g., an epithelial ovarian cancer), the vaccination stepcomprises distally administering the first composition at a site in anorgan system that is not the ovary, e.g., the liver, kidney, etc. Theterm “organ” or “organ system” as used herein refers to a group oftissues with similar functions. Examples of organ systems include,without limitation, the muscular system, the digestive system (e.g.,stomach, small intestine, large intestine, liver, pancreas, etc.), therespiratory system (e.g., lungs), the urinary system (e.g., kidneys,bladder, etc.), the reproductive organs (e.g., male and femalereproductive system, ovaries, placenta, prostate, etc.), the endocrinesystem, the circulatory system, the nervous system (e.g., central andperipheral nervous systems), and the integumentary system (e.g., skin,subcutaneous tissue).

In certain embodiments, the vaccination step comprises distallyadministering the first composition at a site contralateral to the tumorsite. In certain embodiments, the vaccination comprises administering afirst composition at a site contralateral to the tumor (a site in whichthe tumor resides). For example, if the tumor resides at or in an ovary,the vaccination step comprises distally administering the firstcomposition at or in the contralateral ovary. For example, if the tumorresides at or in the left ovary, the vaccination step comprises distallyadministering the first composition to the right ovary. For example, ifthe tumor resides at or in an ovary, the vaccination step comprisesadministering a first composition at or in the contralateral ovary. Forexample, if the tumor resides at or in the left ovary, the vaccinationstep comprises administering a first composition to the right ovary.

In certain embodiments, a method as described herein comprises one ormore vaccination steps. In certain embodiments, a second, a third, afourth, a fifth, a sixth, a seventh, or more vaccination steps areperformed. The skilled artisan will recognize that any, if any,subsequent vaccination steps are performed, the subsequent vaccinationsteps are envisioned to incorporate any of the embodiments of avaccination step described herein.

In certain embodiments, the tumor-marking step comprises intratumorallyor peri-tumorally administering the second composition. In certainembodiments, the tumor-marking step comprises administering a secondcomposition to the subject at the tumor site. In certain embodiments,the tumor-marking step comprises administering a second composition intothe tumor or proximal to the tumor. Accordingly, use of an antigenicpolypeptide described herein prepared for intratumoral delivery asdescribed herein, is provided.

Also provided is a method for eliciting an immune response against asubject suffering from a tumor, comprising the steps of administering toa subject suffering from a tumor a pharmaceutically effective amount ofan antigenic polypeptide, or a nucleic acid encoding said polypeptide,prepared for intratumoral delivery; and administering to said subject apharmaceutically effective amount of an immunogenic compositioncomprising said polypeptide as an immunogen, or comprising a nucleicacid encoding said immunogen, and optionally one or morepharmaceutically-acceptable carriers, adjuvants, excipients and/ordiluents. In certain embodiments, the (i) polypeptide/nucleic acidprepared for intratumoral delivery, (ii) the immunogenic composition,and (iii) the medical use as described herein.

Such a method may further comprise the step of allowing an MHC peptideantigen complex to be produced from said polypeptide followingintratumoral delivery of said polypeptide, or said nucleic acid encodingsaid polypeptide, prepared for intratumoral delivery.

In certain embodiments, administration of the first composition and thesecond composition according to a method as described herein, elicits aT cell mediated immune response against the antigenic polypeptide or theMHC peptide antigen complex.

Also provided herein is a method for treating a tumor in a subject inneed, comprising: (1) a vaccination step comprising distallyadministering a first composition comprising an antigenic polypeptide ora nucleic acid encoding the antigenic polypeptide, wherein theadministration is performed distal to the tumor site; and (2) atumor-marking step comprising intratumorally or peri-tumorallyadministering a second composition comprising an antigenic polypeptideor a nucleic acid encoding the antigenic polypeptide. Accordingly, incertain embodiments, provided herein is a method for treating a tumor ina subject in need, comprising: (1) a vaccination step comprisingdistally administering a first composition comprising a non-tumorantigen or a nucleic acid encoding the non-tumor antigen, wherein theadministration is performed distal to the tumor site; and (2) atumor-marking step comprising intratumorally or peri-tumorallyadministering a second composition comprising the non-tumor antigen or anucleic acid encoding the non-tumor antigen. Also provided herein is amethod for treating a tumor in a subject in need, comprising: (1) avaccination step comprising administering a first composition to thesubject at a site distal to a tumor site, wherein the first compositioncomprises a non-tumor antigen or a nucleic acid encoding the non-tumorantigen; and (2) a tumor-marking step comprising administering a secondcomposition to the subject at the tumor site, wherein the secondcomposition comprises the non-tumor antigen or a nucleic acid encodingthe non-tumor antigen. Accordingly, in certain embodiments, providedherein is a method for treating a tumor in a subject in need,comprising: (1) a vaccination step comprising administering a firstcomposition to the subject at a site distal to a tumor site, wherein thefirst composition comprises a non-tumor antigen or a nucleic acidencoding the non-tumor antigen; and (2) a tumor-marking step comprisingadministering a second composition to the subject at the tumor site,wherein the second composition comprises the non-tumor antigen or anucleic acid encoding the non-tumor antigen.

Also provided herein is a method for generating an immune responseagainst a tumor in a subject in need, comprising: (1) a vaccination stepcomprising distally administering a first composition comprising anantigenic polypeptide or a nucleic acid encoding the antigenicpolypeptide, wherein the administration is performed distal to the tumorsite; and (2) a tumor-marking step comprising intratumorally orperi-tumorally administering a second composition comprising anantigenic polypeptide or a nucleic acid encoding the antigenicpolypeptide. Accordingly, in certain embodiments, provided herein is amethod for generating an immune response against a tumor in a subject inneed, comprising: (1) a vaccination step comprising distallyadministering a first composition comprising a non-tumor antigen or anucleic acid encoding the non-tumor antigen, wherein the administrationis performed distal to the tumor site; and (2) a tumor-marking stepcomprising intratumorally or peri-tumorally administering a secondcomposition comprising the non-tumor antigen or a nucleic acid encodingthe non-tumor antigen. Also provided herein is a method for generatingan immune response against a tumor in a subject in need, comprising: (1)a vaccination step comprising administering a first composition to thesubject at a site distal to a tumor site, wherein the first compositioncomprises a non-tumor antigen or a nucleic acid encoding the non-tumorantigen; and (2) a tumor-marking step comprising administering a secondcomposition to the subject at the tumor site, wherein the secondcomposition comprises the non-tumor antigen or a nucleic acid encodingthe non-tumor antigen. Accordingly, in certain embodiments, providedherein is a method for generating an immune response against a tumor ina subject in need, comprising: (1) a vaccination step comprisingadministering a first composition to the subject at a site distal to atumor site, wherein the first composition comprises a non-tumor antigenor a nucleic acid encoding the non-tumor antigen; and (2) atumor-marking step comprising administering a second composition to thesubject at the tumor site, wherein the second composition comprises thenon-tumor antigen or a nucleic acid encoding the non-tumor antigen.

Also provided is a method for eliciting or directing an immune responseagainst a tumor in a subject in need, comprising: (1) a vaccination stepcomprising distally administering a first composition comprising anantigenic polypeptide or a nucleic acid encoding the antigenicpolypeptide, wherein the administration is performed distal to the tumorsite; and (2) a tumor-marking step comprising intratumorally orperi-tumorally administering a second composition comprising anantigenic polypeptide or a nucleic acid encoding the antigenicpolypeptide. Accordingly, in certain embodiments, provided herein is amethod for eliciting or directing an immune response against a tumor ina subject in need, comprising: (1) a vaccination step comprisingdistally administering a first composition comprising a non-tumorantigen or a nucleic acid encoding the non-tumor antigen, wherein theadministration is performed distal to the tumor site; and (2) atumor-marking step comprising intratumorally or peri-tumorallyadministering a second composition comprising the non-tumor antigen or anucleic acid encoding the non-tumor antigen. Also provided is a methodfor eliciting or directing an immune response against a tumor in asubject in need, comprising: (1) a vaccination step comprisingadministering a first composition to the subject at a site distal to atumor site, wherein the first composition comprises a non-tumor antigenor a nucleic acid encoding the non-tumor antigen; and (2) atumor-marking step comprising administering a second composition to thesubject at the tumor site, wherein the second composition comprises thenon-tumor antigen or a nucleic acid encoding the non-tumor antigen.Accordingly, in certain embodiments, provided herein is a method foreliciting or directing an immune response against a tumor in a subjectin need, comprising: (1) a vaccination step comprising administering afirst composition to the subject at a site distal to a tumor site,wherein the first composition comprises a non-tumor antigen or a nucleicacid encoding the non-tumor antigen; and (2) a tumor-marking stepcomprising administering a second composition to the subject at thetumor site, wherein the second composition comprises the non-tumorantigen or a nucleic acid encoding the non-tumor antigen.

In certain embodiments, the antigenic polypeptide of a method asdescribed herein is CRM197. Accordingly, also provided herein is amethod for treating a tumor in a subject in need, comprising: (1) avaccination step comprising administering a first composition to thesubject at a site distal to a tumor site, wherein the first compositioncomprises CRM197 or a nucleic acid encoding CRM197; and (2) atumor-marking step comprising administering a second composition to thesubject at the tumor site, wherein the second composition comprisesCRM197 or a nucleic acid encoding CRM197. Also provided herein is amethod for generating an immune response against a tumor in a subject inneed, comprising: (1) a vaccination step comprising administering afirst composition to the subject at a site distal to a tumor site,wherein the first composition comprises CRM197 or a nucleic acidencoding CRM197; and (2) a tumor-marking step comprising administering asecond composition to the subject at the tumor site, wherein the secondcomposition comprises CRM197 or a nucleic acid encoding CRM197. Alsoprovided is a method for eliciting or directing an immune responseagainst a tumor in a subject in need, comprising: (1) a vaccination stepcomprising administering a first composition to the subject at a sitedistal to a tumor site, wherein the first composition comprises CRM197or a nucleic acid encoding CRM197; and (2) a tumor-marking stepcomprising administering a second composition to the subject at thetumor site, wherein the second composition comprises CRM197 or a nucleicacid encoding CRM197.

In certain embodiments, the vaccination step and the tumor-marking stepare temporally separated. Accordingly, in certain embodiments, thevaccination step is performed prior to the tumor-marking step. Incertain embodiments, the tumor-marking step is performed subsequent tothe vaccination step. In certain embodiments, a certain time has elapsedafter the vaccination step before the tumor-marking step is performed.In certain embodiments, the amount of time elapsed after the vaccinationstep is sufficient for the subject to mount an immune response to theantigenic polypeptide comprised within the administered firstcomposition. In certain embodiments, the time between the vaccinationstep and the tumor-marking step is sufficient for an immune response tobe mounted as a result of the vaccination step.

For example, a primary immune response can be mounted as a result of thevaccination step. In the case of a primary immune response, it may takeabout 7 days to about 21 days to mount the primary immune response. Inanother example, a secondary immune response can be mounted as a resultof the vaccination step, e.g., in response to an antigenic polypeptidefor which the subject has pre-existing immunity against. In the case ofa secondary immune response, it may take about 2 days to about 3 days tomount the secondary immune response. Accordingly, in certainembodiments, the time between the vaccination step and the tumor-markingstep is from about 1 day to about 21 days, from about 1 day to about 22days, from about 1 day to about 23 days, from about 1 day to about 24days, from about 1 day to about 3 weeks, from about 1 day to about 4weeks, from about 1 day to about 5 weeks, from about 1 day to about 10weeks, from about 1 day to about 15 weeks, from about 1 day to about 20weeks, from about 1 day to about 25 weeks, from about 1 day to about 30weeks, from about 1 day to about 35 weeks, from about 1 day to about 40weeks, from about 1 day to about 45 weeks, from about 1 day to about 50weeks, from about 1 day to about 1 year, from about 1 day to about 2years, from about 1 day to about 3 years, from about 1 day to about 4years, from about 1 day to about 5 years, from about 1 day to about 10years, from about 1 day to about 15 years, from about 1 day to about 20years, from about 1 day to about 25 years, from about 1 day to about 30years, from about 1 day to more than about 30 years, and any interveningamount of time thereof. In certain embodiments, the time between avaccination step and the tumor-marking step is about 1 day to about 1month, 14 days to about 2 months, 1 month to about 3 months, 2 months toabout 5 months, 4 months to about 6 months, 5 months to about 7 months,6 months to about 8 months, 7 months to about 9 months, 8 months toabout 10 months, 9 months to about 11 months, 10 months to about 12months, 11 months to about 13 months, 12 months to about 14 months, 13months to about 15 months, 14 months to about 16 months, 15 months toabout 17 months, 16 months to about 18 months, 17 months to about 19months, 18 months to about 20 months, 19 months to about 21 months, 20months to about 22 months, 21 months to about 23 months, 22 months toabout 24 months, 3 months to about 1 year, 6 months to about 1 year, 1year to about 2 years, 1.5 years to about 3 years, 2 years to about 3.5years, 2.5 years to about 4 years, 3 years to about 4.5 years, 3.5 yearsto about 5 years, 4 years to about 5.5 years, 4.5 years to about 6years, 5 years to about 6.5 years, 5.5 years to about 7 years, 6 yearsto about 7.5 years, 6.5 years to about 8 years, 7 years to about 8.5years, 7.5 years to about 9 years, 8 years to about 9.5 years, 8.5 yearsto about 10 years, and any intervening range of time thereof.

In certain embodiments, the time between the vaccination step and thetumor-marking step is about 1 day, about 2 days, about 3 days, about 4days, about 5 days, about 6 days, about 7 days, about 8 days, about 9days, about 10 days, about 11 days, about 12 days, about 13 days, about14 days, about 15 days, about 16 days, about 17 days, about 18 days,about 19 days, about 20 days, about 21 days, about 4 weeks, about 5weeks, about 6 weeks, about 7 weeks, about 8 weeks, about 9 weeks, about10 weeks, about 20 weeks, about 30 weeks, about 40 weeks about 50 weeks,about 1 year, about 2 years, about 3 years, about 4 years, about 5years, about 10 years, about 15 years, about 20 years, about 25 years,about 30 years, or more, and any intervening amount of time thereof. Incertain embodiments, the time between the vaccination step and thetumor-marking step is about 2 days to about 21 days. In certainembodiments, the time between the vaccination step and the tumor-markingstep is about 2 days to about 3 days. In certain embodiments, the timebetween the vaccination step and the tumor-marking step is about 7 daysto about 21 days.

The contents of the documents referred to throughout the presentdisclosure are each incorporated herein by reference in their entirety.

For the purpose of clarity and a concise description, features aredescribed herein as part of the same or separate aspects and embodimentsthereof. For instance, embodiments relating to polypeptides may alsoapply to nucleic acids encoding such polypeptides, and vice versa. Thesame applies for instance to embodiments that relate to medical usesdefined in product for use, use and method format. While the presentinvention has been described with reference to the specific embodimentsthereof, it should be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted withoutdeparting from the true spirit and scope of the invention. It will bereadily apparent to those skilled in the art that other suitablemodifications and adaptations of the methods described herein may bemade using suitable equivalents without departing from the scope of theembodiments disclosed herein. In addition, many modifications may bemade to adapt a particular situation, material, composition of matter,process, process step or steps, to the objective, spirit and scope ofthe present invention. All such modifications are intended to be withinthe scope of the claims appended hereto. Having now described certainembodiments in detail, the same will be more clearly understood byreference to the following examples, which are included for purposes ofillustration only and are not intended to be limiting.

Sequences

SEQ ID NO: 1: Diphtheria toxin GADDVVDSSKSFVMENFSSYHGTKPGYVDSIQKGIQKPKSGTQGNYDDDWKGFYSTDNKYDAAGYSVDNE NPLSGKAGGVVKVTYPGLTKVLALKVDNAETIKKELGLSLTEPLMEQVGTEEFIKRFGDGASRVVLSLPF AEGSSSVEYINNWEQAKALSVELEINFETRGKRGQDAMYEYMAQACAGNRVRRSVGSSLSCINLDWDVIR DKTKTKIESLKEHGPIKNKMSESPNKTVSEEKAKQYLEEFHQTALEHPELSELKTVTGTNPVFAGANYAA WAVNVAQVIDSETADNLEKTTAALSILPGIGSVMGIADGAVHHNTEEIVAQSIALSSLMVAQAIPLVGEL VDIGFAAYNFVESIINLFQVVHNSYNRPAYSPGHKTQPFLHDGYAVSWNTVEDSIIRTGFQGESGHDIKI TAENTPLPIAGVLLPTIPGKLDVNKSKTHISVNGRKIRMRCRAIDGDVTFCRPKSPVYVGNGVHANLHVA FHRSSSEKIHSNEISSDSIGVLGYQKTVDHTKVNSKLSLFFEIKS SEQ ID NO: 2: Receptor-binding domain of diphtheriatoxin (amino acids 385-535 of SEQ ID NO: 1)KTQPFLHDGYAVSWNTVEDSIIRTGFQGESGHDIK ITAENTPLPIAGVLLPTIPGKLDVNKSKTHISVNGRKIRMRCRAIDGDVTFCRPKSPVYVGNGVHANLHV AFHRSSSEKIHSNEISSDSIGVLGYQKTVDHTKVNSKLSLFFEIKS SEQ ID NO: 3: Receptor-binding domain of diphtheriatoxin (amino acids 387-535 of SEQ ID NO: 1)QPFLHDGYAVSWNTVEDSIIRTGFQGESGHDIKIT AENTPLPIAGVLLPTIPGKLDVNKSKTHISVNGRKIRMRCRAIDGDVTFCRPKSPVYVGNGVHANLHVAF HRSSSEKIHSNEISSDSIGVLGYQKTVDHTKVNSKLSLFFEIKS

EXPERIMENTAL EXAMPLES Materials and Methods

Generation of DCOne Mature Dendritic Cells (mDC)

DCOne progenitors (as deposited with the DSMZ under accession numberDSMZ ACC3189 on 15 Nov. 2012) were differentiated and matured accordingto the procedure described in WO2009019320 A2, the disclosure of whichis incorporated by reference herein in its entirety. Cells were countedand phenotypic analysis of DCOne mDC cells was performed using flowcytometry (FACSVerse; BDBiosciences).

Culture of Ovarian Cancer Cells

OV90 ovarian cancer cell were cultured in medium199/MCDB105 medium (1:1)containing 15% FBS and 2% P/S) in an incubator at 37° C. with 5% CO₂OV90 cells were obtained from ATCC.

Uptake of Foreign Antigens by DCOne mDC

Uptake by DCOne mDC was assessed for three different foreign antigens ata final concentration of 10 μg/mL for 4 hours and 24 hours duringmaturation. 750.000 cells were seeded into 6 well plates for eachcondition. The antigens used were CRM197-Alexa488, subunit KLH-FITC andβ-galactosidase-FITC. CRM197-Alexa488 was purchased from FinaBiosolutions. Subunit KLH was purchased from Stellar BiotechnologiesInc. β-galactosidase was purchased from Roche. Subunit KLH andβ-galactosidase were conjugated in-house to fluorochrome fluoresceinisothiocyanate (FITC) using a FITC labelling kit according tomanufacturer's protocol. Uptake of foreign antigens was assessed by flowcytometry. 0.08% Trypan blue was used to quench externally boundprotein, to visualize only the internalized protein.

Labelling of Tumor Cells with Foreign Antigens

The labelling of OV90 ovarian cancer cells was assessed for threedifferent foreign proteins at a final concentration of 10 μg/mL for 4hours and 24 hours. 100.000 cells were seeded into 96 well plates foreach condition. The proteins used were CRM197-Alexa488, Subunit KLH-FITCand β-galactosidase-FITC. Labelling of tumor cells in vitro was assessedby flow cytometry as mentioned above for DCOne mDC cells.

Humanized U87-MG Glioblastoma Mouse Model

Four-week-old immunodeficient female NOD/Shi-scid/IL-2Rynullimmunodeficient mouse strain (NCG; Taconic) were engrafted withintravenous (IV) injection of 5e4 cord blood-derived CD34+ hematopoieticstem and progenitor cells (French Blood Bank) two days after chemicalmyeloablative treatment. Humanized mice were enhanced for dendritic cellpopulations with a GM-CSF/IL3/1L4 hydrodynamic boost and Flt3Lrecombinant protein. After 7 days mice were inoculated subcutaneously inthe right flank with 1e⁶ U87-MG glioblastoma cells/mouse (Sigma Aldrich)for tumor engraftment. Approximately 15 days after tumor engraftmentmice were randomised and divided into different vaccination groupsincluding 5 mice per group. All mice received 1 intraperitoneal (i.p.)vaccination and one intratumoral (i.t.) injection marking the tumor.

Mice received 100 μg KLH per i.p. injection or a 100 μl PBS i.p.injection, and were injected with 200.000 KLH-loaded DCOne mDCs i.t. or100 μg KLH in 50 μl i.t. according to following schedule:

-   -   Group 1 (PBS/KLH) received one i.p. PBS vaccination (on day 1        after randomization), and one i.t. injection with KLH (on day 8        after randomization);    -   Group 2 (KLH/KLH) received one i.p. KLH vaccination (on day 1        after randomization), and one i.t. injection with KLH (on day 8        after randomization);    -   Group 3 (PBS/KLH loaded DCOne) received one i.p. PBS vaccination        (on day 1 after randomization), and one i.t. injection with KLH        loaded DCOne mDC (on day 8 after randomization);    -   Group 4 (KLH/KLH loaded DCOne) received one i.p. KLH vaccination        (on day 1 after randomization), and one i.t. injection with KLH        loaded DCOne mDC (on day 8 after randomization).

Subunit KLH was purchased from Stellar Biotechnologies Inc. Tumor growthreduction and induction of immune responses were measured.

Humanized A375 Melanoma Mouse Model

After humanization with CD34⁺ stem cells and hydrodynamic boost withcytokines as described above, mice were inoculated subcutaneously in theright flank with 2e⁶ A375 melanoma cells/mouse (Sigma Aldrich) for tumorengraftment. Approximately 15 days after tumor engraftment mice wererandomized and divided into different vaccination groups including 5mice per group. The mice received two intraperitoneal (i.p.)vaccinations and thereafter one intratumoral (i.t.) injection formarking the tumor.

Mice received 100 μg KLH in 100 μl per i.p. injection or a 100 μl PBSi.p. injection, and were injected with 200.000 KLH-loaded DCOne mDCs or100 μg KLH in 50 μl i.t. according to the following schedule:

-   -   Group 1 (PBS/KLH) received two i.p. PBS vaccinations (on days 1        and 8 after randomization), and one i.t. injection with KLH (on        day 15 after randomization);    -   Group 2 (KLH/KLH) received two i.p. KLH vaccinations (on days 1        and 8 after randomization), and one i.t. injection with KLH (on        day 15 after randomization);    -   Group 3 (PBS/KLH loaded DCOne) received two i.p. PBS        vaccinations (on days 1 and 8 after randomization), and one i.t.        injection with KLH loaded DCOne mDC (on day 15 after        randomization);    -   Group 4 (KLH/KLH loaded DCOne) received two i.p. KLH        vaccinations (on days 1 and 8 after randomization), and one i.t.        injection with KLH loaded DCOne mDC (on day 15 after        randomization).

Subunit KLH was purchased from Stellar Biotechnologies Inc. Tumor growthreduction and vaccination induced immune responses were measured.

Example 1. Uptake of Foreign Proteins Uptake of Subunit KLH-FITC byDCOne mDC

DCOne mDC cells were loaded with fluorochrome-conjugated subunit KLHduring maturation process for 4 hours and 24 hours as described in thematerial and methods section. The internalization of subunit KLH wasanalysed using flow cytometer. Trypan blue quenches the cellsurface-bound antigen and was used to distinguish between surface-boundantigen and internalized antigen. The observed internalization ofsubunit KLH-FITC by DCOne mDC after 4 hrs was 54.6±8.8%, and 49.9±9.8%with trypan blue and after 24 hours 86.1±7.0%, and 81.7±8.0% with trypanblue indicating effective antigen uptake by DCOne mDC (FIG. 1A).

Labelling of OV90 Tumor Cells with Subunit KLH

OV90 ovarian carcinoma cells were cultured with subunit KLH-FITC for 4hours and 24 hours as described in the material and methods section. Itwas observed that 13.5±2.6%, labelling of OV90 for 4 hours of which7.5±1.0% of cells with intracellular antigen as demonstrated byquenching of surface-bound subunit KLH-FITC signal with trypan blue, andafter 24 hours 16.5±11.5% of OV90 cells were labelled with antigen with9.5±3.8% of antigen inside the cells (FIG. 1B).

Uptake of β-Galactosidase-FITC by DCOne mDC

DCOne mDCs were incubated with β-galactosidase-FITC for 4 hrs and 24 hrsas described in the materials and methods section. The uptake ofβ-galactosidase-FITC was measured using flow cytometry in the absence orpresence of trypan blue in order to distinguish between extracellularlybound and internalized β-galactosidase-FITC. FIG. 2A depicts that after4 hrs incubation 39.7±10.7% of DCOne mDC have internalizedβ-galactosidase-FITC as the trypan blue quenching hardly affected thesignal (34.5±10.2%) indicating intracellular localization ofβ-galactosidase-FITC in DCOne mDC. The internalisation ofβ-galactosidase-FITC by DCOne mDC was increased after 24 hours i.e.,57.6±10.2%, and 49.9±13.0% with trypan blue indicating intracellularβ-galactosidase-FITC.

Labelling of OV90 by β-Galactosidase-FITC

The labelling of ovarian cancer cell line OV-90 withβ-galactosidase-FITC after 4 hours and 24 hours was 11.3±8.9% (6.0±4.6%with trypan blue) and 10.4±4.2%, (6.5±3.6% with trypan blue)respectively showing both surface-bound and intracellular presence ofβ-galactosidase-FITC (FIG. 2B).

Uptake of CRM197 by DCOne mDC

During the maturation process, DCOne mDC cells were cultured withCRM197-Alexa488 for 4 and 24 hours as described in the materials andmethods section. After 4 and 24 hours uptake of antigen CRM-197 by DCOnemDCs were analysed using a flow cytometer in the presence and absence oftrypan blue as mentioned in above sections. 90.6±5.4% and 99.4±0.1% ofDCOne mDC were observed to have had efficiently internalized CRM-197after 4 and 24 hours, respectively. Trypan blue quenching did not affectthese results (87.6±8.0 and 99.5±0.2% respectively; FIG. 7A).

Labelling of OV90 Tumor Cells with CRM197

The percentage of CRM197-Alexa488 uptake after 4 hours by OV90 tumorcells was 82.0±2.5%, and after 24 hours labelling increased up to98.2±0.1% (FIG. 3). The trypan blue quenching did not affect the signalindicating that CRM-197 is predominantly present inside the cell(72.7±11.9% and 97.6±1.4% with trypan blue after 4 and 24 hoursrespectively).

The in vitro data of uptake of foreign proteins by DCOne mDCs showedthat DCOne mDCs were very efficient in internalizing foreign protein.All foreign proteins tested, CRM197, KLH and β-galactosidase were takenup very well by DCOne mDCs. DCOne cells can thus be used as a carrierfor vaccination and/or intratumoral delivery of foreign proteins.

The data of uptake of foreign proteins by ovarian cancer cells showedthat ovarian cancer cells were more specific in internalizing foreignprotein as compared to DCOne cells. CRM197 is taken up very efficientlyby receptor-mediated endocytosis (Moya et al. J Cell Biol, 101(2):548-59(1985), the disclosure of which is incorporated by reference herein inits entirety) in tumor cells due to presence of the specific HB-EGFreceptor for diphtheria toxin/CRM197 as described in literature (e.g.,Miyamoto et al. Cancer Sci, 97(5):341-7 (2006) the disclosure of whichis incorporated by reference herein in its entirety), while uptake ofKLH and β-galactosidase is lower. These findings show that a tumor canbe marked by foreign proteins. This is especially the case for CRM197,which can therefore potentially be used as a carrier for tumor markingwith other foreign protein coupled to CRM197.

Example 2. Tumor Growth Inhibition in a Humanized U87-MG GlioblastomaMouse Model and in a Humanized A375 Melanoma Mouse Model

The U87-MG mice received one i.p. vaccination of either PBS or KLH andone i.t. injection to mark the tumor either with KLH or KLH-loaded DCOnemDCs. Tumor growth was monitored three times per week using a digitalcaliper (FIG. 4A). Tumor volumes (in mm3) were calculated according tothe following formula: Volume=(width×length{circumflex over ( )}2)/2. Atday 18, a slowed tumor growth was observed in vaccinated mice ascompared to the mice injected with PBS, with i.t. injection ofKLH-loaded DCOne having the strongest effect (FIG. 4B).

The A375 melanoma mice received two i.p. vaccinations of either PBS orKLH and one i.t. injection to mark the tumor either with KLH orKLH-loaded DCOne mDCs. Tumor growth was monitored three times per weekusing a digital caliper (FIG. 5A). Tumor volumes (in mm3) werecalculated according to the following formula:Volume=(width×length{circumflex over ( )}2)/2. As with the U87-MG mice,it was observed that the vaccinated group of mice had a slowed tumorgrowth compared to the groups injected with PBS (FIG. 5B). This effectwas strongest in the mice treated with KLH/KLH loaded DCOne.

These in vivo data in humanized mice show that vaccination followed byintratumoral injection (tumor marking) leads to slowed tumor growth intwo separate solid tumor models, particularly when tumor marking wascarried out using DCOne mDCs as a carrier. Although not statisticallysignificant, the trend of slowed tumor growth was consistent in twoseparate solid tumor models.

Example 3. T Cell Mediated KLH-Specific Antibody Production

Possible antibody responses against KLH resulting from intratumoralinjection and/or vaccination were quantified by ELISA (DO, D14 andsacrifice). In both U87-MG and A375 mice, no significant difference wasobserved regarding anti-KLH IgM concentration between treated groups andthe PBS control group over time (FIG. 6A-FIG. 6B). However, it wassurprisingly observed that mice from the KLH/KLH loaded DCOne groupproduced significantly more anti-KLH IgG than the PBS control group atsacrifice (FIG. 6C-FIG. 6D). This indicates a T cell-dependent IgM toIgG switch (Geha et al., NEJM, 330:1008-1009 (1994) the disclosure ofwhich is incorporated by reference herein in its entirety).

Example 4. CRM197 Vaccination Materials and Methods

Generation of DCOne Mature Dendritic Cells (mDC)

DCOne progenitor cells (as deposited with the DSMZ under accessionnumber DSMZ ACC3189 on 15 Nov. 2012) were differentiated and maturedaccording to the procedure described in PCT Publication No. WO2009/019320, incorporated herein by reference in its entirety. Cellswere counted and phenotypic analysis of DCOne mDC cells was performedusing flow cytometry (FACSVerse; BDBiosciences).

Culture of Cancer Cells

DCOne AML progenitor cells were cultured in MEMα containing 10% FBS and2% P/S in an incubator at 37° C. with 5% CO₂. OV90 ovarian cancer cellswere cultured in medium199/MCDB105 medium (1:1) containing 15% FBS and2% P/S in an incubator at 37° C. with 5% CO2. OV90 cells were obtainedfrom ATCC. U87MG glioblastoma cancer cells were cultured in EMEM mediumcontaining 10% FBS and 2% P/S in an incubator at 37° C. with 5% CO2.U87MG cells were obtained from Merck.

Uptake of Foreign Antigen CRM197 by DCOne mDC

Uptake by DCOne mDC cells was assessed for foreign antigen at a finalconcentration of 10 μg/mL for 4 hours and 24 hours during maturation.750,000 cells were seeded into 6-well plates for each condition. Theforeign antigen used was CRM197-Alexa488 (Fina Biosolutions). Uptake offoreign antigens was assessed by flow cytometry. 0.08% Trypan blue wasused to quench externally bound protein, to visualize only theinternalized protein.

Labelling of Tumor Cells with Foreign Antigen CRM197

The labelling of DCOne progenitor AML cells, OV90 ovarian cancer cellsand U87MG glioblastoma cancer cells was assessed at a finalconcentration of 10 μg/mL for 4 hours and 24 hours. 100,000 cells wereseeded into 96 well plates for each condition. The foreign antigen usedwas CRM197-Alexa488 (Fina Biosolutions). Labelling of tumor cells invitro was assessed by flow cytometry as mentioned above for DCOne mDCs.

Humanized OV90luc Ovarian Cancer Mouse Model

NSGS were engrafted with intravenous (IV) injection of 5e4 cordblood-derived CD34+ hematopoietic stem and progenitor cells. Mice wereinoculated subcutaneously with 5e6 OV90luc ovarian cancer cellsexpressing luciferase for tumor engraftment. Mice were randomized bytumor volume and divided into different vaccination groups including 5mice per group. The average tumour size at start of vaccination was 80mm³. All mice received 2 intraperitoneal (i.p.) vaccinations and oneintratumoral (i.t.) injection marking the tumor.

Mice received 50 μg CRM197 per i.p. injection or a PBS i.p. injection,and were injected with 25 μg CRM197 i.t. according to the followingschedule:

-   -   Group 1 (PBS/PBS) received two i.p. PBS vaccinations (week 2 and        3 after randomization), and one i.t. injection with PBS (week 4        after randomization).    -   Group 2 (PBS/CRM197) received two i.p. PBS vaccinations (week 2        and 3 after randomization), and one i.t. injection with CRM197        (week 4 after randomization).    -   Group 3 (CRM197/PBS) received two i.p. CRM197 vaccinations (week        2 and 3 after randomization), and one i.t. injection with PBS        (week 4 after randomization).    -   Group 4 (CRM197/CRM197) received two i.p. CRM197 vaccinations        (week 2 and 3 after randomization), and one i.t. injection with        CRM197 (week 4 after randomization).

CRM197 was purchased from Fina Biosolutions. Tumor growth reduction(caliper measurement and BLI imaging) and induction of immune responseswere measured.

Uptake of CRM197 by DCOne mDC

During the maturation process, DCOne mDC cells were cultured withCRM197-Alexa488 for 4 and 24 hours as described in the materials andmethods section. After 4 and 24 hours uptake of antigen CRM-197 by DCOnemDC cells were analysed using a flow cytometer in the presence andabsence of trypan blue as mentioned in above sections. 90.6±5.4% and99.4±0.1% of DCOne mDC cells were observed to have had efficientlyinternalized CRM-197 after 4 and 24 hours, respectively. Trypan bluequenching did not affect these results (87.6±8.0% and 99.5±0.2%respectively; FIG. 7A).

Labelling of DCOne Progenitor Cells with CRM197

The percentage of CRM197-Alexa488 uptake after 4 hours by DCOneprogenitor cells was 94.2±3.3%, and after 24 hours labelling increasedup to 99.5±0.8%. The trypan blue quenching did not affect the signalindicating that CRM197 is predominantly present inside the cell(90.7±7.3% and 98.8±1.7% with trypan blue after 4 and 24 hoursrespectively; FIG. 7B).

Labelling of OV90 Tumor Cells with CRM197

The percentage of CRM197-Alexa488 uptake after 4 hours by OV90 tumorcells was 82.0±2.5%, and after 24 hours labelling increased up to98.2±0.1%. The trypan blue quenching did not affect the signalindicating that CRM197 is predominantly present inside the cell(72.7±11.9% and 97.6±1.4% with trypan blue after 4 and 24 hoursrespectively; FIG. 7C).

Labelling of U87MG Tumor Cells with CRM197

The percentage of CRM197-Alexa488 uptake after 4 hours by U87MG tumorcells was 95.3±2.6%, and after 24 hours labelling increased up to99.4±0.4%. The trypan blue quenching did not affect the signalindicating that CRM197 is predominantly present inside the cell(93.9±4.2% and 98.8±0.7% with trypan blue after 4 and 24 hoursrespectively; FIG. 7D).

Tumor Growth in a Humanized OV90luc Ovarian Cancer Model

Tumor growth was monitored by weekly calliper measurements and opticalimaging from the beginning of treatment. The OV90luc mice received twoi.p. vaccinations of either PBS or CRM197 and one i.t. injection to markthe tumor either with PBS or CRM197. Tumor growth was monitored per weekusing a digital caliper. Tumor volumes (in mm³) were calculated by theellipsoid formula (L×W×H)π/6.

No difference in tumor volume was found in CRM197 vaccinated mice ascompared to the mice injected with PBS (FIG. 8A). Bioluminescence datashowed that CRM197 vaccinated mice followed by i.t. injection of CRM197exhibited a significantly lower bioluminescence intensity (FIG. 8B andFIG. 9). This is indicative of a significant growth arrest of OV90ovarian cancer cells in this CRM197 vaccinated/CRM197 i.t. group.

These in vivo data in humanized mice show that CRM197 vaccinationfollowed by intratumoral injection (tumor marking) of CRM197 leads tocancer cell growth arrest.

Example 5. Proof-of-Concept In Vivo Cytotoxicity CRM197

CRM197 is used to study a tumor antigen-independent prime-boost strategyusing CRM197 as a tumor-independent antigen in a humanized tumor mousemodel. Goals of this study are: optimization of a vaccination protocol;repetition of an earlier experiment using an optimal mouse model forrobust tumor regression; and assessment of tumors usingimmunohistochemistry for immune activation at the tumor site.

Vaccination Strategy

Intraperitoneal vaccination:

(week −1, pre-engraftment; week 1, post-engraftment)

I. Vaccination with saline (6 mice).

II. Vaccination with saline (6 mice).

III. Vaccination with CRM197 (6 mice).

IV. Vaccination with CRM197 (6 mice).

Intratumoral Injection:

(week 3 post-engraftment)

I. Intra-tumoral vaccination with saline (6 mice).

II. Intra-tumoral vaccination with CRM197 (6 mice).

III. Intra-tumoral vaccination with saline (6 mice).

IV. Intra-tumoral vaccination with CRM197 (6 mice).

The studies are performed in mice with an HB-EGF-expressing tumor usingthe U87MG glioblastoma cell line. The clinical readout is tumorregression/clearance and survival. Immunohistochemistry of the tumors isassessed to determine tumor infiltration of immune cells. A serumanalysis is performed to detect anti-CRM antibodies. The vaccinationdose is 50 μg CRM197/mouse. The intratumoral dose is 25 μg CRM197/mouse.

TABLE 1 Tabular overview of the CRM197 experiment Tumor Intratumoral #of engraftment Vaccination (i.p.) injection Group mice Week 0 Week −1&1Week 3 #1 6 U87MG Saline Saline #2 6 U87MG Saline CRM197 #3 6 U87MGCRM197 Saline #4 6 U87MG CRM197 CRM197

1. A method for generating an immune response against a tumor in asubject comprising: a vaccination step comprising administering a firstcomposition to the subject at a site distal to a tumor site, wherein thefirst composition comprises a non-tumor antigen or a nucleic acidencoding the non-tumor antigen; and a tumor-marking step comprisingadministering a second composition to the subject at the tumor site,wherein the second composition comprises the non-tumor antigen or anucleic acid encoding the non-tumor antigen, wherein the time betweenthe vaccination step and the tumor-marking step is between about one dayand about 6 months.
 2. The method of claim 1, optionally wherein: themethod further comprises one or more booster steps each comprisingadministering a booster composition to the subject, wherein the boostercomposition comprises the non-tumor antigen or a nucleic acid encodingthe non-tumor antigen, optionally wherein the one or more booster stepsoccur prior to the tumor-marking step; the tumor marking-step comprisesadministering the second composition into the tumor or proximal to thetumor; the vaccination step comprises administering the firstcomposition via a route selected from the group consisting ofintramuscular, subcutaneous, intravenous, intraarterial,intraperitoneal, intrasternal, intradermal, transcutaneous, transdermal,delivery to the interstitial space of a tissue, and delivery to anon-tumor tissue; the vaccination step comprises administering the firstcomposition into an organ system that is different than the organ systemin which the tumor resides, or the vaccination step comprisesadministering the first composition at a site contralateral to thetumor; the tumor is a solid tumor, optionally wherein the solid tumor isglioblastoma or ovarian cancer; the first composition comprises adendritic cell comprising the non-tumor antigen or a nucleic acidencoding the non-tumor antigen, optionally wherein the dendritic cell isa CD34-positive, CD1a-positive, and CD83-positive mature dendritic cell,optionally wherein the mature dendritic cell is derived from DCOne; thesecond composition is prepared for intratumoral administration; thesecond composition comprises a dendritic cell comprising the non-tumorantigen or a nucleic acid encoding the non-tumor antigen, optionallywherein the dendritic cell is a CD34-positive, CD1a-positive, andCD83-positive mature dendritic cell, optionally wherein the maturedendritic cell is derived from DCOne; the first and second compositionseach optionally comprises one or more pharmaceutically-acceptablecarriers, adjuvants, excipients and/or diluents; the subject is anon-tumor antigen-naïve subject, or wherein the subject has previouslybeen exposed to the non-tumor antigen, optionally wherein the subjecthas previously mounted an immune response against the non-tumor antigen;and/or the subject is a human, or the subject is a domesticated animaland/or an animal suitable for veterinary healthcare. 3-5. (canceled) 6.The method of claim 1, wherein the vaccination step comprisesintradermally administering the first composition, optionally whereinthe first composition is prepared for intradermal injection, optionallywherein the first composition comprises a diluent or solvent acceptablefor intradermal injection. 7-8. (canceled)
 9. The method of claim 1,wherein the vaccination step comprises intramuscularly administering thefirst composition, optionally wherein the first composition is preparedfor intramuscular injection, optionally wherein the first compositioncomprises a diluent or solvent acceptable for intramuscular injection.10-13. (canceled)
 14. The method of claim 1, wherein the vaccinationstep is performed subsequent to the tumor-marking step, or wherein thetumor-marking step is performed subsequent to the vaccination step,optionally wherein: the time between the vaccination step and thetumor-marking step is sufficient for an immune response to be mounted asa result of the vaccination step; and/or the time between thevaccination step and the tumor-marking step is about 2 days to about 21days. 15-23. (canceled)
 24. The method of claim 1, wherein the secondcomposition comprises a tumor targeting component, optionally wherein:the tumor targeting component is a tumor-specific virus, optionallywherein the tumor-specific virus is an oncolytic virus, optionallywherein the tumor-specific virus comprises the non-tumor antigen or anucleic acid encoding the non-tumor antigen; or the tumor targetingcomponent is a tumor-specific nanoparticle, optionally wherein thetumor-specific nanoparticle comprises the non-tumor antigen or a nucleicacid encoding the non-tumor antigen. 25-38. (canceled)
 39. A method forgenerating an immune response against a tumor in a subject comprising: avaccination step comprising administering a first composition to thesubject at a site distal to a tumor site, wherein the first compositioncomprises a non-tumor recall antigen or a nucleic acid encoding thenon-tumor recall antigen; and a tumor-marking step comprisingadministering a second composition to the subject at the tumor site,wherein the second composition comprises the recall antigen or a nucleicacid encoding the recall antigen.
 40. The method of claim 39, optionallywherein: the tumor marking-step comprises administering the secondcomposition into the tumor or proximal to the tumor; the vaccinationstep comprises administering the first composition via a route selectedfrom the group consisting of intramuscular, subcutaneous, intravenous,intraarterial, intraperitoneal, intrasternal, intradermal,transcutaneous, transdermal, delivery to the interstitial space of atissue, and delivery to a non-tumor tissue; the vaccination stepcomprises administering the first composition into an organ system thatis different than the organ system in which the tumor resides, or thevaccination step comprises administering the first composition at a sitecontralateral to the tumor; the tumor is a solid tumor, optionallywherein the solid tumor is glioblastoma or ovarian cancer; the firstcomposition comprises a dendritic cell comprising the recall antigen ora nucleic acid encoding the recall antigen, optionally wherein thedendritic cell is a CD34-positive, CD1a-positive, and CD83-positivemature dendritic cell, optionally wherein the mature dendritic cell isderived from DCOne; the second composition is prepared for intratumoraladministration; the second composition comprises a dendritic cellcomprising the recall antigen or a nucleic acid encoding the recallantigen, optionally wherein the dendritic cell is a CD34-positive,CD1a-positive, and CD83-positive mature dendritic cell, optionallywherein the mature dendritic cell is derived from DCOne the first andsecond compositions each optionally comprises one or morepharmaceutically-acceptable carriers, adjuvants, excipients and/ordiluents; the subject has previously been exposed to the recall antigen,optionally wherein the subject has previously mounted an immune responseagainst the recall antigen; and/or the subject is a human, or thesubject is a domesticated animal and/or an animal suitable forveterinary healthcare.
 41. (canceled)
 42. The method of claim 40,wherein the vaccination step comprises intradermally administering thefirst composition, optionally wherein the first composition is preparedfor intradermal injection, optionally wherein the first compositioncomprises a diluent or solvent acceptable for intradermal injection.43-44. (canceled)
 45. The method of claim 40, wherein the vaccinationstep comprises intramuscularly administering the first composition,optionally wherein the first composition is prepared for intramuscularinjection, optionally wherein the first composition comprises a diluentor solvent acceptable for intramuscular injection. 46-49. (canceled) 50.The method of claim 39, wherein the vaccination step and thetumor-marking step are temporally separated, wherein the vaccinationstep is performed subsequent to the tumor-marking step, or thetumor-marking step is performed subsequent to the vaccination step,optionally wherein the time between the vaccination step and thetumor-marking step is sufficient for an immune response to be mounted asa result of the vaccination step, optionally wherein the time betweenthe vaccination step and the tumor-marking step is about 2 days to about21 days. 51-60. (canceled)
 61. The method of claim 39, wherein thesecond composition comprises a tumor targeting component, optionallywherein: the tumor targeting component is a tumor-specific virus,optionally wherein the tumor-specific virus is an oncolytic virus,optionally wherein the tumor-specific virus comprises the recall antigenor a nucleic acid encoding the recall antigen; the tumor targetingcomponent is a tumor-specific nanoparticle, optionally wherein thetumor-specific nanoparticle comprises the recall antigen or a nucleicacid encoding the recall antigen. 62-74. (canceled)
 75. A method forgenerating an immune response against a tumor in a subject comprising: avaccination step comprising administering a first composition to thesubject at a site distal to a tumor site, wherein the first compositioncomprises a diphtheria toxin or detoxified variant thereof or a nucleicacid encoding the diphtheria toxin or detoxified variant thereof; and atumor-marking step comprising administering a second composition to thesubject at the tumor site, wherein the second composition comprises adiphtheria toxin or detoxified variant thereof or a nucleic acidencoding the diphtheria toxin or detoxified variant thereof.
 76. Themethod of claim 75, optionally wherein: the method further comprises oneor more booster steps each comprising administering a boostercomposition to the subject, wherein the booster composition comprisesthe diphtheria toxin or detoxified variant thereof or a nucleic acidencoding the diphtheria toxin or detoxified variant thereof, optionallywherein the one or more booster steps occur prior to the tumor-markingstep; the diphtheria toxin or detoxified variant thereof is CRM197; thetumor marking-step comprises administering the second composition intothe tumor or proximal to the tumor; the vaccination step comprisesadministering the first composition via a route selected from the groupconsisting of intramuscular, subcutaneous, intravenous, intraarterial,intraperitoneal, intrasternal, intradermal, transcutaneous, transdermal,delivery to the interstitial space of a tissue, and delivery to anon-tumor tissue; the vaccination step comprises administering the firstcomposition into an organ system that is different to the organ systemin which the tumor resides; the vaccination step comprises administeringthe first composition at a site contralateral to the tumor; the tumor isa solid tumor, optionally wherein the solid tumor is glioblastoma orovarian cancer; the first composition comprises a dendritic cellcomprising CRM197 or a nucleic acid encoding CRM197, optionally whereinthe dendritic cell is a CD34-positive, CD1a-positive, and CD83-positivemature dendritic cell, optionally wherein the mature dendritic cell isderived from DCOne; the second composition is prepared for intratumoraladministration; the second composition comprises a dendritic cellcomprising CRM197 or a nucleic acid encoding CRM197, optionally whereinthe dendritic cell is a CD34-positive, CD1a-positive, and CD83-positivemature dendritic cell, optionally wherein the mature dendritic cell isderived from DCOne; the first and second compositions each optionallycomprises one or more pharmaceutically-acceptable carriers, adjuvants,excipients and/or diluents; and/or the subject is a human or the subjectis a domesticated animal and/or an animal suitable for veterinaryhealthcare. 77-80. (canceled)
 81. The method of claim 75, wherein thevaccination step comprises intradermally administering the firstcomposition, optionally wherein the first composition is prepared forintradermal injection, optionally wherein the first compositioncomprises a diluent or solvent acceptable for intradermal injection.82-83. (canceled)
 84. The method of claim 75, wherein the vaccinationstep comprises intramuscularly administering the first composition,optionally wherein the first composition is prepared for intramuscularinjection, optionally wherein the first composition comprises a diluentor solvent acceptable for intramuscular injection. 85-88. (canceled) 89.The method of claim 75, wherein the vaccination step and thetumor-marking step are temporally separated, optionally wherein thevaccination step is performed subsequent to the tumor-marking step, orwherein the tumor-marking step is performed subsequent to thevaccination step, optionally wherein the time between the vaccinationstep and the tumor-marking step is sufficient for an immune response tobe mounted as a result of the vaccination step, optionally wherein thetime between the vaccination step and the tumor-marking step is about 2days to about 21 days. 90-99. (canceled)
 100. The method of claim 75,wherein the second composition comprises a tumor targeting component,optionally wherein: the tumor targeting component is a tumor-specificvirus, optionally wherein the tumor-specific virus is an oncolyticvirus, optionally wherein the tumor-specific virus comprises CRM197 or anucleic acid encoding CRM197; or the tumor targeting component is atumor-specific nanoparticle, optionally wherein the tumor-specificnanoparticle comprises CRM197 or a nucleic acid encoding CRM197.101-115. (canceled)